From: Luis Lavena <luislavena@...>
Date: 2009-01-25T01:03:08+09:00
Subject: Re: Help on SQLITE3-ruby (1.2.3) Windows problem

On Jan 24, 3:08 am, jhs...@gmail.com wrote:
> Your Help please:
>
> I have installed sqlite3 in directory :  c:\tools\sqlite3\
> and performed gem install :  gem install sqlite3-ruby-1.2.3-
> mswin32.gem
>
> test2.rb  program:
> #--------------------------------------------------------------
> require 'rubygems'
> require 'sqlite3/database'
>   require 'sqlite3'
>
>   File.delete "test.db" rescue nil
>
>    db = SQLite3::Database.new( "test.db" )
>  sql = <<SQL
>      create table the_table (
>        a varchar2(30),
>        b varchar2(30)
>      );
>
>      insert into the_table values ( 'one', 'two' );
>      insert into the_table values ( 'three', 'four' );
>      insert into the_table values ( 'five', 'six' );
> SQL
>
>    db.execute_batch( sql )
>
> db.execute( "select * from the_table" ) do |row|
>     p row
>   end
> #-----------------------------------------------------------
>
> ** upon executing the program:  ruby test2.rb
>
>    it can not file sqlite3.dll
>
> But when I move aa copy of sqlite3.dll into the same directory as
> test2.rb
> then everything runs OK.
>
> Question:  How do I condition sqlite3-ruby to load the sqlite3.dll
> from the directory c:\tools\sqlite3?
>
> Thanks for your assistance,
> John

For Windows to load shared libraries (.dll) needs to find those in any
of the directories of PATH, including the directory where the
executable (ruby.exe) is located.

Now, this is similar to LD_LIBRARY_PATH on *nix, but playing with it
is considered harmful [1]

sqlite3-ruby is built on Windows against the binary version of SQLite,
which requires the dll to be found in the PATH.

One alternative is add c:\tools\sqlite3 to the PATH:

SET PATH=%PATH%;C:\tools\sqlite3

The other alternative is put sqlite3.dll binary in the Ruby folder.

[1] http://linuxmafia.com/faq/Admin/ld-lib-path.html

HTH,
--
Luis Lavena