Last modified: 2009-01-14 23:26:00 UTC
There is a ready and tested patch. I am committing and then maintaining it as leonsp.
Created attachment 5678 [details] Diffs and new files for the IBM DB2 support in Couldn't generate one big diff, so generated diffs for each file and put into an analogous directory structure. New files are interspersed with the diffs.
Committed as r45755. (bug 17028) Added support for IBM DB2 database. config/index.php has new interface elements that only show up if PHP has ibm_db2 module enabled. AutoLoader knows about the new DB2 classes. GlobalFunctions has a new constant for DB2 time format. Revision class fixed slightly. Also includes new PHP files containing the Database and Search API implementations for IBM DB2. There was more discussion at this URL: http://lists.wikimedia.org/pipermail/wikitech-l/2008-December/040683.html There needs to be a follow-up bug to address the bits of administrative pages that use the non-cross-database LIMIT statement explicitly instead of calling the Database API limitResult() function.
(In reply to comment #2) > There needs to be a follow-up bug to address the bits of administrative pages > that use the non-cross-database LIMIT statement explicitly instead of calling > the Database API limitResult() function. > You mean IBM DB2 doesn't support LIMIT? I thought LIMIT was supposed to be a standard SQL statement?
MS's SQL Server doesnt' have it in 2000/2005.. Not sure about 2008..
LIMIT isn't standard. DB2 has a FETCH FIRST 10 ROWS ONLY statement. SQL Server has a SELECT TOP 10 statement. Oracle has nothing built-in, but LIMIT can be approximated using nested selects and a row number function in the inner one. The MediaWiki database API has a limitResult($sql, $limit, $offset) function that works around most of these issues, but only if it's used.:-)
(In reply to comment #5) > LIMIT isn't standard. DB2 has a FETCH FIRST 10 ROWS ONLY statement. SQL Server > has a SELECT TOP 10 statement. Oracle has nothing built-in, but LIMIT can be > approximated using nested selects and a row number function in the inner one. > > The MediaWiki database API has a limitResult($sql, $limit, $offset) function > that works around most of these issues, but only if it's used.:-) > Can't you just rewrite LIMIT 50 to FETCH FIRST 50 ROWS ONLY transparently, like DatabaseMySQL rewrites USE INDEX(foo) to FORCE INDEX(foo) ?
That's already being done. I'm not referring to doQuery() $options. Those are handled transparently. The problem is the slew of Special pages that build a SQL statement by hand and then call the raw query() method. If you were to pass a USE INDEX clause to those, it would crash MySQL too. They use hard-coded LIMIT stuff. In the long run, those pages will all be migrated to use the Database API. In the short run, they can be fixed by just using the limitResult() bit of the Database API.
