Yes, iBATIS always uses prepared statements - and I pointed it out for exactly the reason you suggest: Statements are not as limited with regard to batching as PreparedStatements.
The JDBC API is kind of gross here. I'm not sure why they couldn't have created a Batch class that you could add statements to and then execute. It would have been a lot more flexible, and the driver would have more freedom to optimize heterogeneous statements. The whole addBatch() / executeBatch() at the statement level is pretty dumb. But it's what we have to work with. The examples I posted inlined the arguments for clarity, but I guess it had the opposite effect. ;-) Clinton From: Chris McMahon [mailto:[EMAIL PROTECTED] Sent: February-29-08 7:10 PM To: [email protected] Subject: RE: iBATIS and Batch This article: http://java.sun.com/j2se/1.3/docs/guide/jdbc/spec2/jdbc2.1.frame6.html suggests that you can pass heterogeneous SQL statements to the database using the JDBC batch functionality. However, it was less clear that you could do this with PreparedStatements. Does iBATIS always use PreparedStatements even if there are no arguments to pass in? In the examples you gave below, you didn't use arguments in your SQL statements. _____ From: [EMAIL PROTECTED] To: [email protected] Subject: RE: iBATIS and Batch Date: Fri, 29 Feb 2008 14:31:28 -0700 >> So you group things together by table? iBATIS doesn't know what a table is. It groups them by (Prepared) SQL Statement. >> Does the JDBC driver not let you batch update across tables without changing the order? The batching features of JDBC are at the statement level. We maintain the order of the statements, but otherwise it's exactly how the JDBC documentation describes - which is quite vague and more up to the JDBC driver than anything. I believe it's as efficient as it can be, without losing the order of the statements. Clinton From: Chris McMahon [mailto:[EMAIL PROTECTED] Sent: February-29-08 2:07 PM To: [email protected] Subject: RE: iBATIS and Batch So you group things together by table? Does the JDBC driver not let you batch update across tables without changing the order? _____ From: [EMAIL PROTECTED] To: [email protected] Subject: RE: iBATIS and Batch Date: Fri, 29 Feb 2008 11:53:39 -0700 It batches based on the statement. So given this example: INSERT INTO author (id,username, password, email, bio) VALUES (1,'jim','********','[EMAIL PROTECTED]',''); INSERT INTO author (id,username, password, email, bio) VALUES (2,'sally','********','[EMAIL PROTECTED]',null); INSERT INTO blog (id,author_id,title) VALUES (1,1,'Jim Business'); INSERT INTO blog (id,author_id,title) VALUES (2,2,'Bally Slog'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (1,1,'2007-12-05-00.00.00','Corn nuts','I think if I never smelled another corn nut, it would be too soon...'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (2,1,'2008-01-12-00.00.00','Paul Hogan on Toy Dogs','That''s not a dog. THAT''s a dog!'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (3,2,'2007-12-05-00.00.00','Monster Trucks','I think monster trucks are great...'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (4,2,'2008-01-12-00.00.00','Tea Parties','A tea party is no place to hold a business meeting...'); These would be executed with 3 batches. If you mix up the order... INSERT INTO author (id,username, password, email, bio) VALUES (1,'jim','********','[EMAIL PROTECTED]',''); INSERT INTO blog (id,author_id,title) VALUES (1,1,'Jim Business'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (1,1,'2007-12-05-00.00.00','Corn nuts','I think if I never smelled another corn nut, it would be too soon...'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (2,1,'2008-01-12-00.00.00','Paul Hogan on Toy Dogs','That''s not a dog. THAT''s a dog!'); INSERT INTO author (id,username, password, email, bio) VALUES (2,'sally','********','[EMAIL PROTECTED]',null); INSERT INTO blog (id,author_id,title) VALUES (2,2,'Bally Slog'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (3,2,'2007-12-05-00.00.00','Monster Trucks','I think monster trucks are great...'); INSERT INTO post (id,blog_id,created_on,subject,body) VALUES (4,2,'2008-01-12-00.00.00','Tea Parties','A tea party is no place to hold a business meeting...'); It would execute with 6 batches. Doing it any other way would cause the statements to execute out of order, which is a more serious concern and not correctable by the user of the framework. Clinton From: Chris McMahon [mailto:[EMAIL PROTECTED] Sent: February-29-08 11:43 AM To: [email protected] Subject: RE: iBATIS and Batch We use the batch functionality frequently. How is iBATIS determining what is homogeneous and what is heterogeneous? We have a mix of both straight SQL updates and prepared statement updates. _____ From: [EMAIL PROTECTED] To: [email protected] Subject: RE: iBATIS and Batch Date: Fri, 29 Feb 2008 08:58:43 -0700 Unfortunately no... that's possibly something we can consider for future versions. The challenge is that some people have the exact opposite problem. They need the statements to maintain the order of execution. When initially deciding who to help, I decided that preserving the order of execution was more important than performance. I also assumed that if you're using a mixed order of heterogeneous statements, you could probably find a way to order them by type and send them through to make the most of batching. Whereas the opposite wouldn't be true, as if I always just reordered the statements for the sake of performance - there would be no way back. I suppose we could support it as an option, but before that I have to ask: Can you reorder your statements? If not, why not? Clinton From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: February-29-08 8:47 AM To: [email protected] Subject: iBATIS and Batch Recently we have been implementing batched SQL calls using iBatis through JDBC. IT appears that iBatis will reorganize batch statements into homogenous calls and treat them as separate batches.... The problem is that is if you do not serially add the homogenous statements, each 'change' from homogeneity results in a separate batch... Does this sound correct? Is there something we can do to control the batching of heterogeneous calls? Thank you, Christopher _____ Connect and share in new ways with Windows Live. Get it now! <http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_012008 > _____ Helping your favorite cause is as easy as instant messaging. You IM, we give. Learn more. <http://im.live.com/Messenger/IM/Home/?source=text_hotmail_join> _____ Climb to the top of the charts! Play the word scramble challenge with star power. 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