Just wondering, but is there any advantage to trying to manually manage the execution plan cache? I know MSSQL-Server for example caches the execution-plan of every parameterized Query (anything executed with the sp_executesql stored-procedure), which means the majority of ADO and ADO.NET based applications, and no one on that side of the fence would ever worry about such a thing; the server manages that cache itself, exactly as it manages what indexes to keep in memory at any given moment.
So I guess my question is: Is flushing the statements really necessary or are you just working under an assumption the database (Postgres/ MySQL) will blindly allow it to grow to unreasonable levels? On May 15, 4:17 am, Hongli Lai <[EMAIL PROTECTED]> wrote: > Here's an update. I noticed that using prepared statements will indeed > make MySQL queries a bit slower. The unit tests in an unmodified Rails > edge source tree took 18 seconds. After adding prepared statements, > they took 28 seconds. I've been working on optimizing this since > yesterday evening, and I succeeded. > Using prepared statements is only advantageous in MySQL if the > arguments are large (i.e. uploading a large image), so the code will > now fallback to _not_ using prepared statements if it detects that no > argument is larger than 32 KB. The unit tests now take 18 seconds > again, thus eliminating the performance problem entirely. Something > similar can be implemented in other adapters. > > It noticed this comment in activerecord/test/binary_test.rb: > # Without using prepared statements, it makes no sense to test > # BLOB data with SQL Server, because the length of a statement is > # limited to 8KB. > # > # Without using prepared statements, it makes no sense to test > # BLOB data with DB2 or Firebird, because the length of a statement > # is limited to 32KB. > So it does make sense to add support for prepared statements in Rails. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Core" group. To post to this group, send email to rubyonrails-core@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-core?hl=en -~----------~----~----~----~------~----~------~--~---
