Tuesday, December 28, 2004

Server Migration

If you're reading this, you're hitting my new dedicated server. The migration wasn't too bad, although I did change the blog database from SQL Server 2000 to MySQL 4.1.7 which was semi-challenging.


 


ere's the steps I took to migrate from SQL Server to MySQL:



  1. Ran the MySQL script that comes with Ray Camden's blog software to create the database


  2. Downloaded and installed MySQL ODBC driver for Windows on my Windows laptop that I have SQL Server Enterprise Manager installed on


  3. Created a user in MySQL to use for the migration


  4. Created ODBC datasource to the MySQL database


  5. Got an error about the authentication method when I tried to connect via the ODBC driver; this is related to the new password hashing mechanism in MySQL 4.1.


  6. Went to the MySQL command line and reset the user's password to the old hash method:

    SET PASSWORD FOR 'some_user'@'some_host' = OLD_PASSWORD('newpwd');

    You have to do this if you want to connect via ODBC!



  7. Created the ODBC connection again--worked this time


  8. Ran the Export DTS in SQL Server EM and pointed to the MySQL database as the destination



Would have been great if it worked, but there was a minor problem of some sort with the tblBlogComments and tblBlogEntries tables. SQL Server EM was throwing an error about not being able to do a BLOB insert ... not sure what that was all about. I thought maybe it had to do with the ntext datatype in SQL Server, but I experimented with changing that to just text (and nvarchar to just varchar) and it didn't help.


I then went through several iterations of exporting the data from SQL Server to a text file and trying to import that directly into MySQL. I didn't ever quite get the right combination of delimiters, text enclosures, etc. to get it to work right. (I tried 4-5 combinations of things and decided to move on--I'm sure this method is possible however.)


So finally I decided to give MS Access a shot as a migration tool. I'm pretty well-known for cursing Access's very existence, but it appears I have found a use for it after all. ;-) I exported the tblBlogComments and tblBlogEntries tables from SQL Server to Access, then used Access to create new tables and export the data to MySQL through the ODBC connection.


The data got there fine, and I just had to do some minor tweaking of datatypes, nullables, add an index, etc. to get the new tables to match the tables created by Ray's script that ships with the blog software. Then I dropped the old tables, renamed the new tables to the correct name, and bingo--everything worked.


As an aside, I like MS SQL Server, but now that I'm on a dedicated server and it's my money going for the software, I opted for MySQL. I'm a big fan and use MySQL a lot anyway, so this was a natural move for me on my personal site. I'm going to be very anxious to try out the new SQL Server Express 2005 once it's available though.

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