Saari Development

Ruby: Oblongular Number Spirals Solution

2008-01-04T12:11:00.000-08:00


  1 # Oblongular Number Spirals
  2 # http://codegolf.com/oblongular-number-spirals
  3 
  4 class Spiral
  5   attr_accessor :row_num, :col_num, :direction
  6   
  7   def initialize(m, n)
  8     @spiral = []
  9     @value = 0
 10     @row_num = m
 11     @col_num = n
 12     @direction = :right
 13   end
 14   
 15   def get(row, col)
 16     if (row < 0 || row >= row_num || col < 0 || col >= col_num)
 17         raise RangeError.new("Out of Bound : row = #{row} col = #{col}")
 18     end
 19     @spiral[row] ||= Array.new
 20     @spiral[row][col] ||= nil
 21     @spiral[row][col]
 22   end
 23   
 24   def increment_fill(row, col)
 25     @value += 1
 26     fill(row, col, @value)
 27   end
 28   
 29   def fill(row, col, value)
 30     if (row < 0 || row >= row_num || col < 0 || col >= col_num)
 31       raise RangeError.new("Out of Bound : row = #{row} col = #{col}")
 32     end
 33     @spiral[row] ||= Array.new
 34     @spiral[row][col] = value
 35   end
 36   
 37   def populate(x = 0, y = 0)
 38     count = 0
 39     while (1)
 40       increment_fill(x, y)
 41       count += 1
 42       # exit the loop once iteration == total_cells
 43       break if count == row_num * col_num
 44       x, y = next_cell(x, y) 
 45     end
 46   @spiral
 47   end
 48   
 49   def next_cell(row, col)
 50     new_row = row
 51     new_col = col
 52 
 53     case @direction
 54     when :right
 55       new_col = col + 1
 56     when :left
 57       new_col = col - 1
 58     when :down
 59       new_row = row + 1
 60     when :up
 61       new_row = row - 1
 62     end
 63 
 64     if ((new_col >= col_num || new_col < 0))
 65       change_direction
 66       next_cell(row, col)
 67     elsif ((new_row >= row_num || new_row < 0))
 68       change_direction
 69       next_cell(row, col)
 70     elsif (get(new_row, new_col) != nil)
 71       change_direction
 72       next_cell(row, col)
 73     else
 74       return [new_row, new_col]
 75     end
 76   end
 77   
 78   def change_direction
 79     case @direction
 80     when :right
 81       @direction = :down
 82     when :down
 83       @direction = :left
 84     when :left
 85       @direction = :up
 86     when :up
 87       @direction = :right
 88     else
 89       raise ArgumentError.new("Illegal value  for current_direction #{@direction}")
 90     end
 91   end
 92 
 93   def dump
 94    display = ''
 95    @spiral.each do |row|
 96      row.each do |col|
 97        display << sprintf("%3d ", col)
 98      end
 99      display << "\n"
100    end
101    puts display
102   end
103 end
104 
105 if $0 == __FILE__
106   s = Spiral.new(ARGV[1].to_i, ARGV[0].to_i)
107   s.populate
108   s.dump
109 end
110


  1 $:.unshift File.join(File.dirname(__FILE__),'..','lib')
  2 
  3 require 'test/unit'
  4 require 'spiral'
  5 
  6 class TestSpiral < Test::Unit::TestCase
  7   def setup
  8     @spiral = Spiral.new(4, 5)
  9   end
 10 
 11   def test_increment_fill_0_0_first
 12     @spiral.increment_fill(0, 0)
 13     assert_equal(1, @spiral.get(0, 0))
 14   end
 15 
 16   def test_increment_fill_1_1_first
 17     @spiral.increment_fill(1, 1)
 18     assert_equal(1, @spiral.get(1, 1))
 19   end
 20 
 21   def test_increment_fill_successive
 22     @spiral.increment_fill(0,0)
 23     @spiral.increment_fill(0,1)
 24     @spiral.increment_fill(1,1)
 25     assert_equal(3, @spiral.get(1, 1))
 26   end
 27 
 28   def test_get_beyond_limit_raises_exception
 29     assert_raise(RangeError) {
 30       @spiral.get(@spiral.row_num + 1, @spiral.col_num + 1)
 31     }
 32   end
 33 
 34   def test_get_below_zero_raises_exception
 35     assert_raise(RangeError) {
 36       @spiral.get(-1, 0)
 37     }
 38   end
 39 
 40   def test_get_at_limit_raises_exception
 41     assert_raise(RangeError) {
 42       @spiral.get(@spiral.row_num, @spiral.col_num)
 43     }
 44   end
 45 
 46 
 47   def test_unfill_get_with_in_range_does_not_raise_exception
 48     assert_nothing_raised() {
 49       @spiral.get(@spiral.row_num - 1, @spiral.col_num - 1)
 50     }
 51   end
 52 
 53   def test_unfill_get_with_in_range_returns_nil
 54     assert_equal(nil, @spiral.get(@spiral.row_num - 1, @spiral.col_num - 1))
 55   end
 56 
 57   def test_fill_beyond_range_raises_exception
 58     assert_raise(RangeError) {
 59       @spiral.increment_fill(@spiral.row_num + 1, @spiral.col_num + 1)
 60     }
 61   end
 62 
 63   def test_fill_beyond_range_raises_exception
 64     assert_raise(RangeError) {
 65       @spiral.increment_fill(0, -1)
 66     }
 67   end
 68 
 69   def test_fill_at_range_raises_exception
 70     assert_raise(RangeError) {
 71       @spiral.increment_fill(@spiral.row_num, @spiral.col_num)
 72     }
 73   end
 74 
 75   def test_populate
 76     spiral = [
 77           [1, 2, 3, 4, 5],
 78           [14, 15, 16, 17, 6],
 79           [13, 20, 19, 18, 7],
 80           [12, 11, 10, 9, 8]
 81          ]
 82     s = @spiral.populate
 83     assert_equal(spiral, s)
 84   end
 85 
 86   def test_change_directon_right
 87     @spiral.direction = :right
 88     @spiral.change_direction
 89     assert_equal(:down, @spiral.direction)
 90   end
 91 
 92   def test_change_directon_up
 93     @spiral.direction = :up
 94     @spiral.change_direction
 95     assert_equal(:right, @spiral.direction)
 96   end
 97 
 98   def test_next_cell_0_0
 99     x, y = @spiral.next_cell(0,0)
100     assert_equal(0, x)
101     assert_equal(1, y)
102   end
103 
104   def test_next_cell_0_4
105     x, y = @spiral.next_cell(0,4)
106     assert_equal(1, x)
107     assert_equal(4, y)
108   end
109 
110 end
111

Ruby : Time Math Interview Problem With Bug Fixed (still writing test first)

2008-01-02T01:33:00.000-08:00

While discussing my friend Arsalan's C# (seemlessly compiled on my linux machine using mcs)
solution and testing it out I found a bug in my own code that. The problem was when adding
more than 12 hours (> 720 minutes) it was not doing the right thing. The code can still be
refactored for cleaner solution but it is too late at night to do that now. Also, my wife
gave me another idea to convert the time to minutes before adding which I will try out later.

  1  # Without using any built in date or time functions, write a function or method
  2  # that accepts two mandatory arguments. The first argument is a string of the
  3  # format "[H]H:MM {AM|PM}" and the second argument is an integer. Assume the
  4  # integer is the number of minutes to add to the string. The return value of
  5  # the function should be a string of the same format as the first argument.
  6  # For example AddMinutes("9:13 AM", 10) would return "9:23 AM". The exercise
  7  # isn't meant to be too hard. I just want to see how you code. Feel free to
  8  # do it procedurally or in an object oriented way, whichever you prefer. Use
  9  # any language you want. Write production quality code. 
 10  # Question Source: http://blist.com/blog/
 11 
 12  # the following solution was developed using TDD
 13 
 14  require 'test/unit'
 15 
 16  class TestTimeCalc < Test::Unit::TestCase
 17 
 18      def setup
 19          @time = "9:13 AM"
 20      end
 21 
 22      def test_new_time_cal
 23          assert_not_nil(TimeCalc.new)
 24      end
 25 
 26      def test_add_minute_zero
 27          assert_equal(@time, TimeCalc.add_minutes(@time, 0))
 28      end
 29 
 30      def test_add_minute_ten
 31          assert_equal("9:23 AM", TimeCalc.add_minutes(@time, 10))
 32      end
 33 
 34      def test_add_minute_thirteen
 35          assert_equal("9:26 AM", TimeCalc.add_minutes(@time, 13))
 36      end
 37 
 38      def test_add_hour
 39          assert_equal("10:13 AM", TimeCalc.add_minutes(@time, 60))
 40      end
 41 
 42      def test_add_two_hours_fifteen_minutes
 43          assert_equal("11:28 AM", TimeCalc.add_minutes(@time, 135))
 44      end
 45 
 46      def test_add_past_meridiem
 47          # 785 minutes = 13 hours and 5 minutes
 48          assert_equal("10:18 PM", TimeCalc.add_minutes(@time, 785))
 49      end
 50 
 51      def test_alpha_hour_min_format_throws_exception
 52          assert_raise(ArgumentError) { TimeCalc.add_minutes("AB:CD AM", 10) }
 53      end
 54 
 55      def test_bad_meridiem_throws_exception
 56          assert_raise(ArgumentError) { TimeCalc.add_minutes("AB:CD TM", 10) }
 57      end
 58 
 59      def test_hr_greater_than_twelve
 60          assert_raise(ArgumentError) { TimeCalc.add_minutes("13:00 PM", 10) }
 61      end
 62 
 63      def test_min_greater_than_fifty_nine
 64          assert_raise(ArgumentError) { TimeCalc.add_minutes("12:60 PM", 10) }
 65      end
 66 
 67      def test_add_lot_of_minutes
 68        # 1000 minutes = 16 hours and 40 minutes
 69        assert_equal("1:53 AM", TimeCalc.add_minutes(@time, 1000))
 70      end
 71 
 72      def test_add_up_to_noon
 73        # 9:13 AM plus 2 hr 47 min (107)
 74        assert_equal("12:00 PM", TimeCalc.add_minutes(@time, 167))
 75      end
 76 
 77      def test_add_whole_lot_of_minutes
 78        # 9999 minutes = 166 hours and 39 minutes
 79        assert_equal("7:52 AM", TimeCalc.add_minutes(@time, 9999))
 80      end
 81 
 82  end # end class TestTimeCalc
 83 
 84  class TimeCalc
 85 
 86      def self.add_minutes(time, minutes)
 87        (hour, min, meridiem) = parse_time_string(time)
 88 
 89        hour_increment = (min + minutes)/60
 90        min_increment = (min + minutes)%60 - min
 91 
 92        while (hour + hour_increment > 12)
 93          meridiem = (meridiem == 'AM' ? 'PM' : 'AM')
 94          hour_increment -= 12
 95        end
 96 
 97        hour += hour_increment
 98        # special case for 12th hour
 99        meridiem = (meridiem == 'AM' ? 'PM' : 'AM') if hour == 12
100        min += min_increment
101 
102        hour.to_s + ":" + sprintf('%02d', min) + " " + meridiem
103      end
104 
105      private
106 
107      def self.parse_time_string(time)
108          raise ArgumentError unless (matches = time.match(/(\d{1,2}):(\d{1,2})\s+(\w{2})/))
109          matches = time.match(/^(\d{1,2}):(\d{1,2})\s+([A|P]M)$/)
110          hour = matches[1].to_i
111          min = matches[2].to_i
112          meridiem = matches[3]
113          raise ArgumentError unless (hour <= 12)
114          raise ArgumentError unless (min < 60)
115          return [hour, min, meridiem]
116      end
117  end # end class TimeCalc
118 
119 if __FILE__ == $0
120   puts TimeCalc.add_minutes(ARGV[0], ARGV[1].to_i)
121 end
122 

# vim colorscheme = delek

Ruby: One liner to strip the line number from code posted

2007-12-30T20:02:00.000-08:00

In response to my previous post my friend Arsalan posted his C# solution on my shared friend blog SaarayDost

Both my solution and his had line numbers with the code which makes it easy to reference a line number in a discussion but if you want to run and test code it can be painful to strip them out one by one.

I wrote the following quick ruby one liner that can be run on a file after copy-pasting the code and saving it.


 ruby -lne 'puts $_.gsub(/^\s?\d+:?/, "")' ali.rb > ali.rb

I am sure there good be a better more clever way to do this after all TIMTOWDI but here I use the l to remove newline at the end of each line, n to iterate over the given file one line at a time and e to execute the following code string (in quotes, on each line). $_ is the magic variable (a perl legacy in ruby) that magically populated, in this case with the current line of file being processed. gsub simply removed the pattern match in the first argument by the string in the second argument.

While searching for a good description of $_ I also found this interesting link with other useful ruby one-liners.

Update: found another way to achieve the above result. -p option prints the $_ at the end of each iteration.


ruby -lpe '$_.gsub!(/^\s?\d+:?/, "")' ali.rb > ali.rb

Ruby : Time Math Interview Problem Done Test First

2007-12-28T15:18:00.000-08:00

Question from : Blist.com Career Page


  1 # Without using any built in date or time functions, write a function or method
  2 # that accepts two mandatory arguments. The first argument is a string of the
  3 # format "[H]H:MM {AM|PM}" and the second argument is an integer. Assume the
  4 # integer is the number of minutes to add to the string. The return value of
  5 # the function should be a string of the same format as the first argument.
  6 # For example AddMinutes("9:13 AM", 10) would return "9:23 AM". The exercise
  7 # isn't meant to be too hard. I just want to see how you code. Feel free to
  8 # do it procedurally or in an object oriented way, whichever you prefer. Use
  9 # any language you want. Write production quality code. 
 10 # Question Source: http://blist.com/blog/
 11 
 12 # the following solution was developed using TDD
 13 
 14 require 'test/unit'
 15 
 16 class TestTimeCalc < Test::Unit::TestCase
 17 
 18     def setup
 19         @time = "9:13 AM"
 20     end
 21 
 22     def test_new_time_cal
 23         assert_not_nil(TimeCalc.new)
 24     end
 25 
 26     def test_add_minute_zero
 27         assert_equal(@time, TimeCalc.add_minutes(@time, 0))
 28     end
 29 
 30     def test_add_minute_ten
 31         assert_equal("9:23 AM", TimeCalc.add_minutes(@time, 10))
 32     end
 33 
 34     def test_add_minute_thirteen
 35         assert_equal("9:26 AM", TimeCalc.add_minutes(@time, 13))
 36     end
 37 
 38     def test_add_hour
 39         assert_equal("10:13 AM", TimeCalc.add_minutes(@time, 60))
 40     end
 41 
 42     def test_add_two_hours_fifteen_minutes
 43         assert_equal("11:28 AM", TimeCalc.add_minutes(@time, 135))
 44     end
 45 
 46     def test_add_past_meridiem
 47         # 785 minutes = 13 hours and 5 minutes
 48         assert_equal("10:18 PM", TimeCalc.add_minutes(@time, 785))
 49     end
 50 
 51     def test_alpha_hour_min_format_throws_exception
 52         assert_raise(ArgumentError) { TimeCalc.add_minutes("AB:CD AM", 10) }
 53     end
 54 
 55     def test_bad_meridiem_throws_exception
 56         assert_raise(ArgumentError) { TimeCalc.add_minutes("AB:CD TM", 10) }
 57     end
 58 
 59     def test_hr_greater_than_twelve
 60         assert_raise(ArgumentError) { TimeCalc.add_minutes("13:00 PM", 10) }
 61     end
 62 
 63     def test_min_greater_than_fifty_nine
 64         assert_raise(ArgumentError) { TimeCalc.add_minutes("12:60 PM", 10) }
 65     end
 66 
 67 end # end class TestTimeCalc
 68 
 69 class TimeCalc
 70 
 71     def self.add_minutes(time, minutes)
 72       (hour, min, meridiem) = parse_time_string(time)
 73 
 74       hour_increment = (min + minutes)/60
 75       min_increment = (min + minutes)%60 - min
 76       if (hour_increment >= 12)
 77         meridiem = (meridiem == 'AM' ? 'PM' : 'AM')
 78         hour_increment -= 12
 79       end
 80 
 81       hour += hour_increment
 82       min += min_increment
 83 
 84       hour.to_s + ":" + min.to_s + " " + meridiem
 85     end
 86 
 87     private
 88 
 89     def self.parse_time_string(time)
 90         raise ArgumentError unless (matches = time.match(/(\d{1,2}):(\d{1,2})\s+(\w{2})/))
 91         matches = time.match(/^(\d{1,2}):(\d{1,2})\s+([A|P]M)$/)
 92         hour = matches[1].to_i
 93         min = matches[2].to_i
 94         meridiem = matches[3]
 95         raise ArgumentError unless (hour <= 12)
 96         raise ArgumentError unless (min < 60)
 97         return [hour, min, meridiem]
 98     end
 99 
100 end # end class TimeCalc

Vim: Inserting output of unix/linux command

2007-12-23T16:48:00.000-08:00

I had seen other vim experts do this but couldn't remember how they did. Today I finally search and found how to insert the output of a unix/linux command directly in a vim buffer(without copy-pasting).


  :r!ls /home/

or in the visual mode (by pressing V) simply !ls /home/

Simple isn't it and quite useful at times.

Ruby: net/smtp weirdness - to address can't contain dash/hyphen (-)

2007-10-02T17:15:00.000-07:00

This caused me a lot of grief and debugging time.

I am using code like this to send emails from a CGI script:


    Net::SMTP.start('smtp.example.com', 25) do |smtp|
      smtp.open_message_stream('from@example.com', ['dest-address@example.com']) do |f|
        f.puts 'From: from@example.com'
        f.puts 'To: dest-address@example.com'
        f.puts 'Cc: cc-address@example.com'
        f.puts 'Subject: test message'
        f.puts
        f.puts 'This is a test message.'
      end
    end

and this is failing silent in my case.

I have discovered through trial and error that if I remove the -(dash) from the to address it works. Dashes in from or CC addresses does not matter.

Vim: Delete every line in the file that does not match a pattern

2007-09-25T08:52:00.000-07:00

I realized the power of :g much later than many other commands in vim and I think this one has been there even in vi for a long time.

Here is a great tip that covers the virtues of :g in vim:

Tip #227: Power of :g

The reason I ended up with this tip was that I needed to find a simple command that would delete all lines matching a pattern.

I knew how to delete all lines that matched a pattern.


:g/pattern/d

but I was looking for the inverse and I found it :g's cousin :v in the above tip as a user comment.


:v/patter/d

did the job very well. Once again vim saved the day. :-)

*nix: nslookup to resolve an IP to host name

2007-09-12T17:27:00.000-07:00

nslookup is useful to resolve an ip address to a host name in the linux/unix environment.

nslookup - query Internet name servers interactively

Ruby : Where are the gems on ubuntu 7.04

2007-08-08T07:15:00.001-07:00

It took me some time to figure it out where the gems are installed on my ubuntu 7.04 linux machine so I thought I would save it here as a reminder. The ruby gems are stored here:


/var/lib/gems/1.8/gems

What I did to find this is to run gem install without sudo to see the error message:


me@desktop:/usr/lib/ruby/1.8$ gem install rails
Bulk updating Gem source index for: http://gems.rubyforge.org
ERROR:  While executing gem ... (Errno::EACCES)
    Permission denied - /var/lib/gems/1.8/cache/rails-1.2.3.gem

The permission denied message gave me my answer. Who said error messages are not educational?

Hurray!

MySQL and Rails: mysql.sock not found

2007-08-05T23:37:00.000-07:00

I started doing my webapp on my brand new server (ubuntu linux 7.04) and when trying to run my first migration I got the following error message:


rake db:migrate
(in /home/rizvi/projects/somewebapp)
rake aborted!
No such file or directory - /tmp/mysql.sock

Here is a useful mysql command to find out mysql defaults:


mysqladmin --print-defaults
mysqladmin would have been started with the following arguments:
--port=3306 --socket=/var/run/mysqld/mysqld.sock

Here is what solved the problem:


sudo apt-get install libmysql-ruby

Note: The above is an alternative to :

sudo gem install mysql

Now I get:


rake db:migrate
(in /home/rizvi/projects/somewebapp)
rake aborted!
Unknown database 'somewebapp_development'
(See full trace by running task with --trace)

So I need to do the following:


mysqladmin -u root create somewebapp_development -p
mysqladmin -u root create somewebapp_test -p
mysqladmin -u root create somewebapp_production -p

Reference: RailsOnUbuntu

Vim: Turn off gVim toolbar

2007-07-02T09:33:00.000-07:00

I don't know about you but I don't like my gVim real estate to be polluted by toolbar under the menus so in my early days of using gVim I researched and discovered a way to turn them off.

Here is what you need to put in your .gvimrc (or _gvimrc on windows):

" To set the toolbars off (icons on top of the screen)
set guioptions-=T

Vim: Setting height and width of gVim window

2007-07-02T09:23:00.000-07:00

I always struggled with this on my windows Vim and today I saw the fix on a vim users mailing list addressing this exact question.

Here is the way to set height (lines) of gVim (graphical Vim) window:

:set lines=40

and here is how to set width (columns) of gVim windows:

:set columns=80

Ruby: Rotating Image Files Description

2007-06-25T05:48:00.001-07:00

I was looking for a tool that would do the same thing that flick does on upload, that is rotate the files appropriately based on information embedded in the image files.

Finally I decided to just do it!

Since all my photos are on my windows machine that was my platform of choice.

Thankfully RMagick package for windows comes with ImageMagick installer. The only thing tricky was to install the gem file from the locally downloaded gem file.

While searching for EXIF library for Ruby I found quite a few on RubyForge but finally exifr seemed most functional/friendly.

Entry below shows the code I ended up with.

Instructions for outputting the html for the code in gVim on windows:

* :colorscheme delek
* Syntax -> Convert to HTML
* remove html, head and body tags
* paste to blogspot

Ruby: Rotating Image Files Code

2007-06-25T05:43:00.000-07:00


require 'rmagick'
require 'exifr'
require 'pp'

ROTATE_CLOCKWISE = 90
ROTATE_ANTICLOCKWISE = -90

def rotate(file)
  image_exif = EXIFR::JPEG.new(file).exif

  puts "#{file} : #{image_exif[:orientation]}"
  if (image_exif[:orientation] == EXIFR::TIFF::RightTopOrientation)
    degrees = ROTATE_CLOCKWISE
  elsif (image_exif[:orientation] == EXIFR::TIFF::LeftBottomOrientation)
    degrees = ROTATE_ANTICLOCKWISE
  else
    puts "Not rotating #{file}"
    return
  end

  image = (Magick::Image.read(file)).first
  #image.rotate(degrees).write("#{file.split('.').first}_rotated.jpg")
  image.rotate(degrees).write("#{file}")
end

dir = ARGV[0]

Dir.entries(dir).each do |file|
  if (file =~ /jpg/i)
    rotate(File.join(dir, file))
  end
end

Vim: .gvimrc on Mac

2007-05-21T23:33:00.001-07:00


" Copied from $VIMRUNTIME/gvimrc_example.vim

" An example for a gvimrc file.
" The commands in this are executed when the GUI is started.
"
" Maintainer: Bram Moolenaar <Bram@vim.org>
" Last change:  2001 Sep 02
"
" To use it, copy it to
"     for Unix and OS/2:  ~/.gvimrc
"       for Amiga:  s:.gvimrc
"  for MS-DOS and Win32:  $VIM\_gvimrc
"     for OpenVMS:  sys$login:.gvimrc

" Make external commands work through a pipe instead of a pseudo-tty
"set noguipty

" set the X11 font to use
" set guifont=-misc-fixed-medium-r-normal--14-130-75-75-c-70-iso8859-1

set ch=2    " Make command line two lines high

set mousehide   " Hide the mouse when typing text
set antialias   " setting antialiasing for guifont

" Make shift-insert work like in Xterm
map <S-Insert> <MiddleMouse>
map! <S-Insert> <MiddleMouse>

" Only do this for Vim version 5.0 and later.
if version >= 500

  " I like highlighting strings inside C comments
  let c_comment_strings=1

  " Switch on syntax highlighting if it wasn't on yet.
  if !exists("syntax_on")
    syntax on
  endif

  " Switch on search pattern highlighting.
  set hlsearch

  " For Win32 version, have "K" lookup the keyword in a help file
  "if has("win32")
  "  let winhelpfile='windows.hlp'
  "  map K :execute "!start winhlp32 -k <cword> " . winhelpfile <CR>
  "endif

  " Set nice colors
  " background for normal text is light grey
  " Text below the last line is darker grey
  " Cursor is green, Cyan when ":lmap" mappings are active
  " Constants are not underlined but have a slightly lighter background
  highlight Normal guibg=grey90
  highlight Cursor guibg=Green guifg=NONE
  highlight lCursor guibg=Cyan guifg=NONE
  highlight NonText guibg=grey80
  highlight Constant gui=NONE guibg=grey95
  highlight Special gui=NONE guibg=grey95

  " over riding the above settings with my preferred settings
  colorscheme torte
  set background=dark
endif

Vim: .vimrc on Mac

2007-05-21T23:20:00.001-07:00


" Copied from $VIMRUNTIME/vimrc_example.vim

" An example for a vimrc file.
"
" Maintainer: Bram Moolenaar <Bram@vim.org>
" Last change:  2002 Sep 19
"
" To use it, copy it to
"     for Unix and OS/2:  ~/.vimrc
"       for Amiga:  s:.vimrc
"  for MS-DOS and Win32:  $VIM\_vimrc
"     for OpenVMS:  sys$login:.vimrc

" When started as "evim", evim.vim will already have done these settings.
if v:progname =~? "evim"
  finish
endif

" Use Vim settings, rather then Vi settings (much better!).
" This must be first, because it changes other options as a side effect.
set nocompatible

" allow backspacing over everything in insert mode
set backspace=indent,eol,start

if has("vms")
  set nobackup    " do not keep a backup file, use versions instead
else
  set backup    " keep a backup file
endif
set history=50    " keep 50 lines of command line history
set ruler   " show the cursor position all the time
set showcmd   " display incomplete commands
set incsearch   " do incremental searching
set number    " show line number
set tabstop=2
set shiftwidth=2
set expandtab
set textwidth=80
set background=dark

set gfn=Monaco:h14  " setting to a good Mac OS X font

" For Win32 GUI: remove 't' flag from 'guioptions': no tearoff menu entries
" let &guioptions = substitute(&guioptions, "t", "", "g")

" Don't use Ex mode, use Q for formatting
map Q gq

" This is an alternative that also works in block mode, but the deleted
" text is lost and it only works for putting the current register.
"vnoremap p "_dp

" Switch syntax highlighting on, when the terminal has colors
" Also switch on highlighting the last used search pattern.
if &t_Co > 2 || has("gui_running")
  syntax on
  set hlsearch
endif

" Only do this part when compiled with support for autocommands.
if has("autocmd")

  " Enable file type detection.
  " Use the default filetype settings, so that mail gets 'tw' set to 72,
  " 'cindent' is on in C files, etc.
  " Also load indent files, to automatically do language-dependent indenting.
  filetype plugin indent on

  " Put these in an autocmd group, so that we can delete them easily.
  augroup vimrcEx
  au!

  " For all text files set 'textwidth' to 78 characters.
  autocmd FileType text setlocal textwidth=78

  " When editing a file, always jump to the last known cursor position.
  " Don't do it when the position is invalid or when inside an event handler
  " (happens when dropping a file on gvim).
  autocmd BufReadPost *
    \ if line("'\"") > 0 && line("'\"") <= line("$") |
    \   exe "normal g`\"" |
    \ endif
  autocmd BufRead *.rhtml set filetype=eruby

  augroup END

else

  set autoindent    " always set autoindenting on

endif " has("autocmd")

Vim: _vimrc on windows

2007-05-21T23:08:00.000-07:00


set nocompatible
source $VIMRUNTIME/vimrc_example.vim
source $VIMRUNTIME/mswin.vim
behave mswin

set diffexpr=MyDiff()
function MyDiff()
  let opt = '-a --binary '
  if &diffopt =~ 'icase' | let opt = opt . '-i ' | endif
  if &diffopt =~ 'iwhite' | let opt = opt . '-b ' | endif
  let arg1 = v:fname_in
  if arg1 =~ ' ' | let arg1 = '"' . arg1 . '"' | endif
  let arg2 = v:fname_new
  if arg2 =~ ' ' | let arg2 = '"' . arg2 . '"' | endif
  let arg3 = v:fname_out
  if arg3 =~ ' ' | let arg3 = '"' . arg3 . '"' | endif
  let eq = ''
  if $VIMRUNTIME =~ ' '
    if &sh =~ '\<cmd'
      let cmd = '""' . $VIMRUNTIME . '\diff"'
      let eq = '"'
    else
      let cmd = substitute($VIMRUNTIME, ' ', '" ', '') . '\diff"'
    endif
  else
    let cmd = $VIMRUNTIME . '\diff'
  endif
  silent execute '!' . cmd . ' ' . opt . arg1 . ' ' . arg2 . ' > ' . arg3 . eq
endfunction

set guifont=Lucida_Console:h10:cANSI
colorscheme torte

Find all writeable files in a directory tree

2007-03-20T12:28:00.000-07:00

I needed to find if I forgot to p4 edit (or add) any of the files I was working with and needed to find all writeable files in my current directory structure (recursively). I did a quick search and found a newsgroup entry that helped (referenced below) but here is what you need to do :

find . -type f -perm +200

4 is for readable(r)
2 is for writeable (w)
1 is for executable (x)

Do

man find

and search for perm to find more of what more you can do.

Ref: http://www.cygwin.com/ml/cygwin/2003-05/msg00502.html
Here is a better reference: Searching for files by permission

Windows: Making my laptop *nix friendly

2006-11-28T17:41:00.000-08:00

I usually do most of my development on my Linux machine and only use my Windows XP laptop for using Outlook (mail and calendaring) and browsing (Firefox, of course).

I decided to work from home due to weather conditions and had to use my laptop more and finally took the steps to make my laptop more unix friendly.

I already had my favorite editor Vim installed on the machine and ruby one click install (which did not required the forbidden admin priviliges thank God) made quick experimenting easy while I was commuting to work. Also rubygems installation work pretty smoothly (similar to on a linux/mac osx system) on windows also.

I already had configured my laptop to use have tab completion for windows lesser shell (cmd or Command Prompt) so cd into directories was a breeze.

Two things that I missed the most still were ls (which I often typed and got error on windows shell) and typing vi filename and opening file and I was fed up with using edit to open files all the time which is far from a decent text editor at least by my standards.

Finally I was motivated enough to do something about these. Here is what I did:

Added the path to the directory where vim was installed to my environment variable:

1. Right Click on 'My Computer' and click 'Properties'
2. Click on 'Advanced' tab and click 'Environment Variables' button, click 'PATH' if already exists or create new if it is not already there.
3. Add the absolute path of directory where vim.exe exists at the end (semi-colo {;} separated list).

Create shortcuts for vi and ls

1. Now open command prompt (Start -> Run -> cmd -> OK)
2. cd into the directory where vim is installed (e.g. C:\>cd "Program Files\Vim\vim70")
3. edit vi.bat
4. type "C:\Progra~1\Vim\vim70\vim.exe %1 %2 %3" save and exit (Alt - F - X) the file
4a. %1, %2 ... are the arguments passed to the bat (shell) script
Since I am lazy I will create the ls bat also here but you can create it in any directory in your path
5. vi ls.bat (now you can use your new shortcut)
6. type "dir %1" save and exit (:wq) the file

Enjoy!

Ruby: Finding the absolute path of running script

2006-11-06T20:56:00.000-08:00

I needed to use the full/absolute path of the script/program to a library for access control. I had not done something like this before so here is my trail of discovery:

$0

I started with $0, which in ruby is one of those magic variables that contain the name of the program that was executed from the command line.

The problem with $0 is that it does not necessary have the absolute path, it has whatever the user used which could be relative or absolute.

__FILE__

Then I found __FILE__ which was not exactly what I was looking for as it would give you the file name of the current file so when executing library routine it would be the name of the library file not the original executable file that the user ran.

File.expand_path

After some research I found File.expand_path which essentially did the trick if you use it with $0. So File.expand_path $0 would give you the absolute path of the calling program.

Pathname.new.realpath.to_s

On a parallel note I found Pathname.new.realpath.to_s also but that require you to require 'pathname' and also it resolved a symbolic link to real path which was not desired in my case.

Dir.chdir

One caveat with File.expand_path which an experienced rubyist pointed out that if a script does a Dir.chdir then File.expand_path would not work as it essentially prepends the cwd (current working directory) to $0 but even the fellow rubyist couldn't think of a better way to do this so File.expand_path was my eventual solution and it works!

*nix shell: stty for terminal line settings

2006-10-09T13:12:00.000-07:00

I don't think this is a new discovery but just a reminder for myself when I encounter this problem again.

I encountered this problem when I was using irb (interactive ruby shell) and for some odd reason when I typed backspace it was printing ^H and worse when I hit enter irb crashes. When I returned to my shell backspace seems to be working fine.

This is not exclusive problem with irb although the crashing part is but the solution I think would work in cases where shell is demonstrating this wierd behavior.

I did a quick *nix command:


stty

and displayed that I have


erase ^?

In order to fix this problem here is what I did:


stty erase ^H

Note:^H are not the two characters but typed Ctrl-V Ctrl-H

Ruby: ri Command Line Help

2006-09-28T14:44:00.000-07:00

Looking up help on ruby methods and classes from the command line sounds simple but can be very useful if you don't know or don't remember.

ri is the equivalent of 'man' command in unix (I always confuse this with rdoc which is for generating html documentation, I think perldoc has something to do with this confusion).

Some example commands are


prompt> ri Class
prompt> ri alias_method

In case multiple classes have the same method and you are searching for a method


prompt> ri method_missing

ri will show a message like this:


More than one method matched your request. You can refine
your search by asking for information on one of:

   Delegator#method_missing, Kernel#method_missing

You can then look for the specific method using:


prompt> ri Kernel#method_missing

Update: I just discovered that Class#method is for instance methods, if you want to look help class methods then it is done using Class::method.

Example:


ri Hash::new        # shows details of the Hash class's new method
ri Hash#delete      # shows details of the hash instance's delete method

Also found this interesting reference:
Ruby RI - Using Ruby's RI Documentation Reader

Tools: Saving Putty Configuration

2006-07-10T19:09:00.000-07:00

Putty is a decent terminal emulation program for MS Windows operatings system:

It can be downloaded from:
http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html

At the time of this writing the latest release version was 0.58.

Putty does not need to be installed and does not create seperate directory to store its configuration, all its configuration is stored in the windows registry.

Start -> Run -> regedit (OK/Enter)

HKEY_CURRENT_USER -> Software -> SimonTatham -> Putty

You can save the configuration by right clicking on SimonTatham and selecting Export from the context menu.

To restore setting, transport the file to the new machine and double click on it after downloading Putty.

Ruby: Searching for a variable string using grep

2006-04-28T18:52:00.000-07:00

I was looking for a way to search for a variable string inside a ruby method and I think I have found _a_ solution.


def print_line_containing(file, str)
  File.open(file).grep(/#{str}/).each do |line| puts "#{line}" end
end

def print_line_containing(file, str1, str2)
  File.open(file).grep(/#{str1}\s+#{str2}/).each do |line| puts "#{line}" end
end

Vim: Indentation (tab) Settings

2006-02-27T14:18:00.000-08:00

In the same discussion that I discovered the settings for ruby specific settings I found some tips on best setting of tab and shift related settings


sts=2 sw=2 ts=8 et

Here is my understanding of the settings:

sts = smart tab stops - these are useful when you hit tab for indenting, when you hit backspace you will go back a sts lenth rather than one space at a time because of et is enabled

sw = shift width - this is useful when you do << or >> for indenting

ts = tab stop - would render the real tab (tab character) properly if found in your code

et = expand tabs - replaces/exapnds tab to spaces

Vim: Setting different indentation for Ruby files

2006-02-27T12:58:00.000-08:00

Adding this to .vimrc file should result in shift-width set to two when editing ruby files:


autocmd FileType ruby setlocal  sw=2

*nix: Text Files Commands

2006-02-25T03:24:00.000-08:00

This post saved the day for some work related stuff:

Week 101 - Unix Commands Reference (7 March 2005)

It talks about:

split ... split a file into many files
sort ... sort the lines of a file into alphabetic order
uniq ... filter out repeated lines of a file
join ... perform a database join on files
paste ... merge corresponding lines of two file
comm ... display lines common to two files
diff ... compare two files
diff3 ... compares three files
sdiff ... compare and merge two files
zdiff, bzdiff ... diff zipped, bzipped files

Ruby: using irb and ri as a exploratory learning device

2006-02-22T14:48:00.000-08:00


irb> Kernel.methods.each do |method| puts method; system "/usr/local/bin/ri --no-pager Kernel##{method}"; ch = STDIN.getc; break if (ch.chr == 'q') end

Once you enter this just keep hit enter until you want to quit, at that point hit 'q' and enter.

Still some kinks to be worked out but it is a start

Update:
Found this interesting link: http://www.rubygarden.org/ruby?Irb/TipsAndTricks on http://www.rubyweeklynews.org/

vim extracting first column (space delimited)

2006-02-19T11:26:00.000-08:00

Just figured out how to extract a single (first) column from a file containing text

:%s/^$\w\+$\.\*/\1/g

I am sure there is a better way to do this but this is best I can get for now. I don't like the excessive escaping vim requires in regex.

PS: Just figured out that you have to have:

:set nomagic

for the above subsitution to work.

vimrc update - showmatch

2006-02-10T11:28:00.000-08:00

" rediscovered showmatch
set showmatch
" this would show you the matching paren or brace

Rails: Working around Tiger (OS X 10.4) ruby mysql problem

2005-12-11T19:08:00.000-08:00

I was not happy when I found myself stuck try to run scaffolding for the first time, discovering that my previous attempt to fix preinstalled Tiger ruby and that after installing Xcode 2.2 I don't have ruby.h where fixrubyconfig expects (as per the most famous fix Complete Fix for Ruby on Mac OS X 10.4 Tiger which is also mentioned in Agile Web Development with Rails

I was partly heart broken and partly frustrated and hoped that some mac and ruby 'guru' at the upcoming Seattle.rb Hack Night can help.

But then I had a thought and it worked.

I installed the latest stable version of ruby (1.8.3):
Download from: ftp://ftp.ruby-lang.org/pub/ruby/ruby-1.8.3.tar.gz


shell> tar -zxvf ruby-1.8.3.tar.gz
shell> cd ruby-1.8.3
shell> ./configure
shell> make -j5
shell> sudo make install

This installs the new version of ruby in the /usr/local/bin directory on your powerbook

Now I added the new ruby path to my $PATH using
export PATH=/usr/local/bin:$PATH
this would mean that any time a issue a command it would look in /usr/local/bin before /usr/bin where the old (tiger default version is installed). I have also modified my .profile to have a similar PATH in future.

then I downloaded and installed rubygem again:
Download from: http://rubyforge.org/frs/download.php/5207/rubygems-0.8.11.tgz


shell> tar -zxvf rubygems-0.8.11.tgz
shell> cd rubygems-0.8.11
shell> sudo ruby setup.rb

Next I installed rails gem


shell> sudo gem install rails --include-dependencies

Next I installed mysql gem


shell> sudo gem install mysql -- --with-mysql-dir=/usr/local/mysql/

it worked for the first time now giving me a successfully installed message.

Finally I was able to do my scaffolding task as suggested by the book:
from your rails app directory do the following for the existing product table


shell> ruby script/generate scaffold Product Admin

It seems that the on Mac OS X you require a username in your database.yml file (you can't leave it blank otherwise it would default to root) so I had to modify my configuration on last time before seeing the magical command work.

Ruby: I am stuck with OS X Tiger (10.4) Ruby problem and can't install mysql gem

2005-12-11T10:02:00.000-08:00

I have followed the step from http://tech.rufy.com/entry/46 but I get the following error:

mv /usr/local/lib/libreadline.a /usr/local/lib/libreadline.old/usr/bin/install -c -m 644 libreadline.a /usr/local/lib/libreadline.atest -n "ranlib" && ranlib /usr/local/lib/libreadline.amv /usr/local/lib/libhistory.a /usr/local/lib/libhistory.old/usr/bin/install -c -m 644 libhistory.a /usr/local/lib/libhistory.atest -n "ranlib" && ranlib /usr/local/lib/libhistory.atest -d shlib || mkdir shlib( cd shlib ; make all )make[1]: Nothing to be done for `all'.( cd shlib ; make DESTDIR= install )/bin/sh ../support/mkdirs /usr/local/lib/bin/sh ../support/shlib-install -O darwin8.3.0 -d /usr/local/lib -i "/usr/bin/install -c -m 644" libhistory.5.0.dylib/bin/sh ../support/shlib-install -O darwin8.3.0 -d /usr/local/lib -i "/usr/bin/install -c -m 644" libreadline.5.0.dylibinstall: you may need to run ldconfig % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed100 3542k 100 3542k 0 0 193k 0 0:00:18 0:00:18 --:--:-- 233kcan't find header files for ruby.make: *** No targets specified and no makefile found. Stop.

I don't know what do to make MySQL working with Rails

Somebody help me. May be I will take this problem to hack night

MySQL: Display permissions on different databases

2005-12-10T15:35:00.000-08:00

mysql> select Host, DB, User, Select_priv, Insert_priv, Update_priv, Delete_priv, Create_priv, Drop_priv, Alter_priv from db;


+-----------+-------------------+-------+-------------+-------------+-------------+-------------+-------------+-----------+------------+
| Host      | DB                | User  | Select_priv | Insert_priv | Update_priv | Delete_priv | Create_priv | Drop_priv | Alter_priv |
+-----------+-------------------+-------+-------------+-------------+-------------+-------------+-------------+-----------+------------+
| %         | test              |       | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
| %         | test\_%           |       | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
| localhost | depot_development | rizvi | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
| localhost | depot_production  | rizvi | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
| localhost | depot_test        | rizvi | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
| localhost | depot_production  | prod  | Y           | Y           | Y           | Y           | Y           | Y         | Y          |
+-----------+-------------------+-------+-------------+-------------+-------------+-------------+-------------+-----------+------------+

Vim: ERb syntax file for rails view development

2005-12-06T01:00:00.000-08:00

Yesterday I made rhtml (embedded ruby) files kind of working by using the html filetype and I was digging the xml/html tag completion plugin. Today after only one search I ended up on the following useful page:

http://wiki.rubyonrails.com/rails/pages/HowtoUseVimWithRails

Apart from other seemingly useful tips I found the link to the eruby syntax script:
http://www.vim.org/scripts/script.php?script_id=403

I followed the directions and placed the eruby.vim file in my ~/.vim/syntax/ directory and modified the autocmd line from yesterday in my ~/.vimrc to this:

autocmd BufRead *.rhtml set filetype=eruby

Some how the xml/html plugin to complete tags as you type them still work.
I don't see the <% %> tags breaking the html syntax highlighting and they eruby tags are now highlighted (not necessary a preference of mine but I can live with it).

Vim: xml and html auto tag completion

2005-12-04T20:12:00.000-08:00

Downloaded the ftplugin from here:

http://tritarget.com/cgi-bin/viewcvs.cgi/xmledit/ftplugin/xml.vim (pointed to by here: http://www.vim.org/scripts/script.php?script_id=301)

copied the file to ~/.vim/ftplugin/xml.vim

at this point XML completion works (.xml files) but html does not.

once the plugin was triggered and installed witha deleteme.xml file, I followed the instruction at did this:
:help xml-plugin-html

I copy pasted the html.vim file in the help to a new file:
~/.vim/ftplugin/html.vim

and then loaded my rhtml (or any html file that autocmds to filetype html) and the plugin started working

Vim: Adding file extension to a filetype of syntax highlighting

2005-12-04T19:56:00.000-08:00

"Add this line to syntax highlight any rhtml (rails view, ERb) to be displayed with HTML syntax highlighting
autocmd BufRead *.rhtml set filetype=html

Now I have to figure out how to load the matchit plugin that enables auto-complete for HTML tags

MySQL: Creating InnoDB tables, converting tables and verifying

2005-11-20T00:37:00.000-08:00

InnoDB tables support transactions and foriegn keys and are widely used in large MySQL enviroments like slashdot.

I wanted to be able to create innodb tables so I read the relevant section of the manual on innodb

My /etc/my.cnf file (that I copied from $MYSQLDIR/support-files/my-medium.cnf) already had the innodb configuration commented I just uncommented the following lines:


    119 # Uncomment the following if you are using InnoDB tables
    120 # rizvi - uncommented 2005-11-19
    121 innodb_data_home_dir = /usr/local/mysql/data/
    122 innodb_data_file_path = ibdata1:10M:autoextend
    123 innodb_log_group_home_dir = /usr/local/mysql/data/
    124 innodb_log_arch_dir = /usr/local/mysql/data/
    125 # You can set .._buffer_pool_size up to 50 - 80 %
    126 # of RAM but beware of setting memory usage too high
    127 innodb_buffer_pool_size = 16M
    128 innodb_additional_mem_pool_size = 2M
    129 # Set .._log_file_size to 25 % of buffer pool size
    130 innodb_log_file_size = 5M
    131 innodb_log_buffer_size = 8M
    132 innodb_flush_log_at_trx_commit = 1
    133 innodb_lock_wait_timeout = 50

I created one table to test it out using the example given in the manual:


CREATE TABLE customers (a INT, b CHAR (20), INDEX (a)) ENGINE=InnoDB;

It seems using TYPE instead of ENGINE is allowed but is effectively deprecated and not the recommended way.

It seems it is fairly easy to convert an existing table to innodb (or any other supported engines) here is the example from the manual:


ALTER TABLE t ENGINE = INNODB;

Now that I had created a table I wanted to verify that it was created properly as a INNODB tables instead of the default MyISAM. I tried this:


mysql> show full tables;
+----------------+------------+
| Tables_in_test | Table_type |
+----------------+------------+
| customers      | BASE TABLE |
| ino_test       | BASE TABLE |
| testaa         | BASE TABLE |
| testad         | BASE TABLE |
+----------------+------------+
4 rows in set (0.00 sec)

It was strange and misleading as the two pre-existing tables starting with test (MyISAM) were shown as the same type as the new customer INNODB tables. I thought may be I missed a config thing and I made sure I had restared mysqld after the config change.

Finally I figured out the right command to see detailed table information:


mysql> show table status;
+-----------+--------+---------+------------+------+----------------+-------------+-------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-------------------+----------+----------------+----------------------+
| Name      | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length   | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation         | Checksum | Create_options | Comment              |
+-----------+--------+---------+------------+------+----------------+-------------+-------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-------------------+----------+----------------+----------------------+
| customers | InnoDB |      10 | Compact    |    1 |          16384 |       16384 |                 0 |        16384 |         0 |           NULL | 2005-11-19 23:15:51 | NULL                | NULL       | latin1_swedish_ci |     NULL |                | InnoDB free: 4096 kB |
| ino_test  | InnoDB |      10 | Compact    |    0 |              0 |       16384 |                 0 |            0 |         0 |           NULL | 2005-11-20 00:34:18 | NULL                | NULL       | latin1_swedish_ci |     NULL |                | InnoDB free: 4096 kB |
| testaa    | MyISAM |      10 | Fixed      |    7 |             69 |         483 | 19421773393035263 |         1024 |         0 |           NULL | 2005-11-19 01:01:54 | 2005-11-19 01:01:54 | NULL       | latin1_swedish_ci |     NULL |                |                      |
| testad    | MyISAM |      10 | Dynamic    |    1 |             20 |          20 |   281474976710655 |         1024 |         0 |           NULL | 2005-11-19 01:02:02 | 2005-11-19 01:02:06 | NULL       | latin1_swedish_ci |     NULL |                |                      |
+-----------+--------+---------+------------+------+----------------+-------------+-------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-------------------+----------+----------------+----------------------+
4 rows in set (0.11 sec)

That was gratifying to see the two tables I created were showing up rightly as INNODB tables.

Next up is experimenting with the transactions with INNODB tables.

MySQL: Changing password and finding user permissions

2005-11-19T15:51:00.000-08:00

Changing password can be done through the mysql command:

If you have no root password (which is how MySQL comes out of the box) then type the following:

shell> $MYSQLDIR/mysqladmin -u root password newpassword

now if you have a password and want to change it:

shell> $MYSQLDIR/mysqladmin -u root -p password newpassword
Enter password: oldpassword

There drawback to this technique is that your new password is saved in the shell history buffer in clear text which is undesirable but I have not found a better way yet.

Once you have changed the password and you want to see what users exists with what password you can see that by logging into the special "mysql" database as root:

shell> $MYSQLDIR/mysql -u root -p mysql
Enter Password:

Now when you can see all the tables in the special "mysql" database:

mysql> show tables;


mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| func                      |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| host                      |
| proc                      |
| procs_priv                |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      |
+---------------------------+
17 rows in set (0.00 sec)

Look into the user table to see the list of interesting fields as there are a lot of them:


mysql>  describe user;
mysql> describe user;
+-----------------------+-----------------------------------+------+-----+---------+-------+
| Field                 | Type                              | Null | Key | Default | Extra |
+-----------------------+-----------------------------------+------+-----+---------+-------+
| Host                  | char(60)                          | NO   | PRI |         |       |
| User                  | char(16)                          | NO   | PRI |         |       |
| Password              | char(41)                          | NO   |     |         |       |
| Select_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Insert_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Update_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Delete_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Create_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Drop_priv             | enum('N','Y')                     | NO   |     | N       |       |
| Reload_priv           | enum('N','Y')                     | NO   |     | N       |       |
| Shutdown_priv         | enum('N','Y')                     | NO   |     | N       |       |
| Process_priv          | enum('N','Y')                     | NO   |     | N       |       |
| File_priv             | enum('N','Y')                     | NO   |     | N       |       |
| Grant_priv            | enum('N','Y')                     | NO   |     | N       |       |
| References_priv       | enum('N','Y')                     | NO   |     | N       |       |
| Index_priv            | enum('N','Y')                     | NO   |     | N       |       |
| Alter_priv            | enum('N','Y')                     | NO   |     | N       |       |
| Show_db_priv          | enum('N','Y')                     | NO   |     | N       |       |
| Super_priv            | enum('N','Y')                     | NO   |     | N       |       |
| Create_tmp_table_priv | enum('N','Y')                     | NO   |     | N       |       |
| Lock_tables_priv      | enum('N','Y')                     | NO   |     | N       |       |
| Execute_priv          | enum('N','Y')                     | NO   |     | N       |       |
| Repl_slave_priv       | enum('N','Y')                     | NO   |     | N       |       |
| Repl_client_priv      | enum('N','Y')                     | NO   |     | N       |       |
| Create_view_priv      | enum('N','Y')                     | NO   |     | N       |       |
| Show_view_priv        | enum('N','Y')                     | NO   |     | N       |       |
| Create_routine_priv   | enum('N','Y')                     | NO   |     | N       |       |
| Alter_routine_priv    | enum('N','Y')                     | NO   |     | N       |       |
| Create_user_priv      | enum('N','Y')                     | NO   |     | N       |       |
| ssl_type              | enum('','ANY','X509','SPECIFIED') | NO   |     |         |       |
| ssl_cipher            | blob                              | NO   |     |         |       |
| x509_issuer           | blob                              | NO   |     |         |       |
| x509_subject          | blob                              | NO   |     |         |       |
| max_questions         | int(11) unsigned                  | NO   |     | 0       |       |
| max_updates           | int(11) unsigned                  | NO   |     | 0       |       |
| max_connections       | int(11) unsigned                  | NO   |     | 0       |       |
| max_user_connections  | int(11) unsigned                  | NO   |     | 0       |       |
+----------------------+-----------------------------------+------+-----+---------+-------+
37 rows in set (0.05 sec)

Here is a query that would tell you user have permissions to certain operations on your database from different host:


mysql> select host, user, select_priv, insert_priv, delete_priv, create_priv, drop_priv, alter_priv from user;
+----------------+------+-------------+-------------+-------------+-------------+-----------+------------+
| host           | user | select_priv | insert_priv | delete_priv | create_priv | drop_priv | alter_priv |
+----------------+------+-------------+-------------+-------------+-------------+-----------+------------+
| localhost      | root | Y           | Y           | Y           | Y           | Y         | Y          |
| AliPower.local | root | Y           | Y           | Y           | Y           | Y         | Y          |
| AliPower.local |      | N           | N           | N           | N           | N         | N          |
| localhost      |      | N           | N           | N           | N           | N         | N          |
+----------------+------+-------------+-------------+-------------+-------------+-----------+------------+
4 rows in set (0.00 sec)

It seems the blank user name is there to allow to run mysql shell without a user.

Results of MySQL sql-bench run-all-tests

2005-11-19T15:16:00.000-08:00

AliPower:/usr/local/mysql/sql-bench rizvi$ sudo perl run-all-tests
Benchmark DBD suite: 2.15
Date of test: 2005-11-19 1:04:10
Running tests on: Darwin 8.2.0 Power Macintosh
Arguments:
Comments:
Limits from:
Server version: MySQL 5.0.15 standard log
Optimization: None
Hardware:

alter-table: Total time: 49 wallclock secs ( 0.14 usr 0.05 sys + 0.00 cusr 0.00 csys = 0.19 CPU)
ATIS: Total time: 99 wallclock secs (22.24 usr 1.19 sys + 0.00 cusr 0.00 csys = 23.43 CPU)
big-tables: Total time: 112 wallclock secs (13.17 usr 2.98 sys + 0.00 cusr 0.00 csys = 16.15 CPU)
connect: Total time: 511 wallclock secs (93.54 usr 40.86 sys + 0.00 cusr 0.00 csys = 134.40 CPU)
create: Total time: 302 wallclock secs (12.95 usr 3.32 sys + 0.00 cusr 0.00 csys = 16.27 CPU)
insert: ^A^A^H^HTotal time: 2860 wallclock secs (706.16 usr 90.47 sys + 0.00 cusr 0.00 csys = 796.63 CPU)
select: Total time: 1554 wallclock secs (94.04 usr 8.91 sys + 0.00 cusr 0.00 csys = 102.95 CPU)
transactions: Test skipped because the database doesn't support transactions
wisconsin: Total time: 20 wallclock secs ( 4.09 usr 0.96 sys + 0.00 cusr 0.00 csys = 5.05 CPU)

All 9 test executed successfully

Totals per operation:
Operation seconds usr sys cpu tests
alter_table_add 21.00 0.03 0.01 0.04 100
alter_table_drop 20.00 0.03 0.01 0.04 91
connect 52.00 13.47 3.87 17.34 10000
connect+select_1_row 72.00 15.01 4.48 19.49 10000
connect+select_simple 57.00 14.28 4.31 18.59 10000
count 42.00 0.07 0.00 0.07 100
count_distinct 35.00 0.69 0.10 0.79 1000
count_distinct_2 37.00 0.71 0.10 0.81 1000
count_distinct_big 56.00 10.01 0.23 10.24 120
count_distinct_group 37.00 2.63 0.13 2.76 1000
count_distinct_group_on_key 45.00 0.78 0.09 0.87 1000
count_distinct_group_on_key_parts 38.00 2.63 0.12 2.75 1000
count_distinct_key_prefix 29.00 0.62 0.08 0.70 1000
count_group_on_key_parts 27.00 1.42 0.08 1.50 1000
count_on_key 437.00 23.66 3.19 26.85 50100
create+drop 57.00 3.73 0.89 4.62 10000
create_MANY_tables 80.00 2.73 0.61 3.34 10000
create_index 4.00 0.00 0.00 0.00 8
create_key+drop 73.00 3.92 0.95 4.87 10000
create_table 0.00 0.01 0.01 0.02 31
delete_all_many_keys 77.00 0.02 0.00 0.02 1
delete_big 0.00 0.00 0.00 0.00 1
delete_big_many_keys 77.00 0.01 0.00 0.01 128
delete_key 4.00 0.56 0.27 0.83 10000
delete_range 17.00 0.00 0.00 0.00 12
drop_index 4.00 0.01 0.00 0.01 8
drop_table 0.00 0.00 0.00 0.00 28
drop_table_when_MANY_tables 34.00 1.17 0.39 1.56 10000
insert 139.00 16.62 7.40 24.02 350768
insert_duplicates 30.00 4.33 1.86 6.19 100000
insert_key 150.00 14.83 4.42 19.25 100000
insert_many_fields 41.00 0.76 0.18 0.94 2000
insert_select_1_key 7.00 0.00 0.00 0.00 1
insert_select_2_keys 10.00 0.00 0.00 0.00 1
min_max 26.00 0.04 0.01 0.05 60
min_max_on_key 47.00 21.64 2.93 24.57 85000
multiple_value_insert 7.00 0.63 0.02 0.65 100000
once_prepared_select 54.00 12.57 2.67 15.24 100000
order_by_big 52.00 29.66 0.76 30.42 10
order_by_big_key 54.00 29.68 0.89 30.57 10
order_by_big_key2 49.00 29.25 0.75 30.00 10
order_by_big_key_desc 56.00 29.65 0.92 30.57 10
order_by_big_key_diff 56.00 29.61 0.77 30.38 10
order_by_big_key_prefix 47.00 28.92 0.68 29.60 10
order_by_key2_diff 7.00 2.69 0.08 2.77 500
order_by_key_prefix 4.00 1.46 0.06 1.52 500
order_by_range 5.00 1.47 0.06 1.53 500
outer_join 91.00 0.01 0.00 0.01 10
outer_join_found 86.00 0.00 0.00 0.00 10
outer_join_not_found 85.00 0.01 0.00 0.01 500
outer_join_on_key 68.00 0.01 0.00 0.01 10
prepared_select 89.00 28.69 4.03 32.72 100000
select_1_row 52.00 8.10 3.33 11.43 100000
select_1_row_cache 54.00 7.51 3.19 10.70 100000
select_2_rows 92.00 9.87 3.82 13.69 100000
select_big 46.00 29.48 0.69 30.17 80
select_big_str 36.00 8.18 10.00 18.18 10000
select_cache 296.00 6.03 0.78 6.81 10000
select_cache2 297.00 6.13 0.78 6.91 10000
select_column+column 30.00 5.07 2.16 7.23 100000
select_diff_key 1.00 0.20 0.03 0.23 500
select_distinct 25.00 4.26 0.17 4.43 800
select_group 99.00 3.19 0.25 3.44 2911
select_group_when_MANY_tables 58.00 1.39 0.48 1.87 10000
select_join 4.00 1.25 0.06 1.31 100
select_key 161.00 60.41 8.83 69.24 200000
select_key2 160.00 60.61 8.63 69.24 200000
select_key2_return_key 141.00 56.93 8.14 65.07 200000
select_key2_return_prim 151.00 59.07 8.41 67.48 200000
select_key_prefix 182.00 62.99 9.28 72.27 200000
select_key_prefix_join 25.00 11.19 0.28 11.47 100
select_key_return_key 146.00 56.97 8.30 65.27 200000
select_many_fields 71.00 12.41 2.79 15.20 2000
select_range 264.00 20.34 0.64 20.98 410
select_range_key2 26.00 6.93 0.74 7.67 25010
select_range_prefix 28.00 7.25 0.78 8.03 25010
select_simple 32.00 6.16 2.86 9.02 100000
select_simple_cache 34.00 5.89 2.83 8.72 100000
select_simple_join 5.00 1.50 0.07 1.57 500
update_big 23.00 0.00 0.00 0.00 10
update_of_key 38.00 3.58 1.53 5.11 50000
update_of_key_big 36.00 0.07 0.03 0.10 501
update_of_primary_key_many_keys 38.00 0.04 0.02 0.06 256
update_with_key 100.00 13.41 6.40 19.81 300000
update_with_key_prefix 41.00 8.91 3.00 11.91 100000
wisc_benchmark 5.00 2.44 0.22 2.66 114
TOTALS 5489.00 928.49 147.93 1076.42 3425950
AliPower:/usr/local/mysql/sql-bench rizvi$

MySQL Post Installation

2005-11-19T01:06:00.000-08:00

Here is the command again for running mysql server:
sudo /usr/local/mysql/bin/mysqld_safe --user=mysql &

The documentation would tell you to change the root password immediately but wait until you are through the section about installing Perl support (DBI and DBD::mysql) and run the MYSQLDIR /sql-bench perl run-all-tests.

Both the CPAN installation and run-all-tests expect a blank password for root user.

If you have already changed your password you have two options:
1. force install DBD::mysql (on perl -MCPAN -e shell) OR
2. change your root password back to blank using :-> mysqladmin -u root -p password ''

The test under sql-bench are very processor intensive and take some time so be patient with them. (you might need to do sudo perl run-all-tests).

Setting up MySQL

2005-11-19T00:09:00.000-08:00

It seems like a trivial thing but I had never installed or administered my own database so MySQL was definitely a first for me.

The motivation was to start developing my first Rails app on my powerbook.

I will add some random notes here and clean them up later:

I installed MySQL 5.0 from binary installation for Mac OS X.

MySQL 5.0 HTML Documentation was helpful. I also downloaded the pdf version.

Installed directory: /user/local/mysql called MYSQLDIR hereon

Copied MYSQLDIR/support-files/my-medium.cnf to /etc/my.cnf

added these two lines in my ~/.profile

alias mysql=/usr/local/mysql/bin/mysql
alias mysqladmin=/usr/local/mysql/bin/mysqladmin

AliPower:/usr/local/mysql rizvi$ sudo scripts/mysql_install_db --user=mysql
Password:
Installing all prepared tables
051119 0:25:47 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/mysql-standard-5.0.15-osx10.4-powerpc/data/ is case insensitive
Fill help tables
051119 0:25:47 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/mysql-standard-5.0.15-osx10.4-powerpc/data/ is case insensitive

To start mysqld at boot time you have to copy support-files/mysql.server
to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
./bin/mysqladmin -u root password 'new-password'
./bin/mysqladmin -u root -h AliPower.local password 'new-password'
See the manual for more instructions.

NOTE: If you are upgrading from a MySQL <= 3.22.10 you should run
the ./bin/mysql_fix_privilege_tables. Otherwise you will not be
able to use the new GRANT command!

You can start the MySQL daemon with:
cd . ; ./bin/mysqld_safe &

You can test the MySQL daemon with the benchmarks in the 'sql-bench' directory:
cd sql-bench ; perl run-all-tests

Please report any problems with the ./bin/mysqlbug script!

The latest information about MySQL is available on the web at
http://www.mysql.com
Support MySQL by buying support/licenses at https://order.mysql.com
AliPower:/usr/local/mysql rizvi$

My .vimrc (updated 2006-02-10)

2005-10-12T20:41:00.000-07:00

" Ali Rizvi's Vim Settings


set number
set shiftwidth=4

set ruler

set incsearch
set hlsearch
set textwidth=80

" from lindes:
syntax on
hi Comment term=bold ctermfg=Cyan guifg=Cyan
set listchars=tab:»·,trail:·,eol:¬
set autoindent

" from benji fisher to turn on the matchit plugin automatically and more
filetype plugin on

" explicity map file extension .t to perl syntax instead of tads
" which is autodetected by filetype plugin on
" This line should always be after filetype plugin
autocmd BufNewFile,BufRead *.t set syntax=perl

" to show real tabs and spaces in file
set list
set listchars=tab:»·,trail:^,eol:¬
"set listchars=tab:>-,trail:-

"to add spaces instead of tabs
set expandtab

" evil, bad! -- hard tabs should be 8 chars... --lindes
" set tabstop=4
" _but_ we can use this:
set smarttab

" show matching opening brace/paren when typing close
set showmatch

"use arrow keys to move to previous and next buffers
nmap <C-R> :bn<CR>
nmap <C-L> :bp<CR>

My gvimrc

2005-10-12T20:29:00.000-07:00

 " Ali Rizvi's Graphical ViMproved configuration file
 "
 " Revision: 1.0 - 09/15/2003

 " Always have syntax highlighting in with the gui:
 syntax on
 " To set the toolbars off (icons on top of the screen)
 set guioptions-=T

New blog dedicated to my software development adventures

2005-10-11T21:16:00.000-07:00

I was feeling the need of something like this for a long time but officially I thought of this new blog today on the bus commuting back home.

I started with looking for a better blogging website then livejournal or blogger both of whom I have used and am using for my various blogs. Two of the blogs that I frequently update are my personal blog and Maryam's (my daughter) photoblog.

I discoverd today how hard it could be to find a good name that is available for your new blog on popular sites like blogger. My main problem with livejournal is that it only gives you one blog per user/login. Blogger gives you as many as you want but livejournal has some nice native clients that you can install and enjoy using for your blog posting. My favorite livejournal client for Windows is Semagic.

The result of searching for the ideal blogging website did not give me many options and I finally decided to give with the tried and tested blogger. Now I need to find a nice client for blogger/blogspot to make it easy on myself to blog.