RE: Debugging Queries
Hi, The easiest way to do this is to use p6spy. Please see the FAQ at http://db.apache.org/ojb/docu/faq.html#traceProfileSQL Cheers, Charles. -Original Message- From: Tino Schöllhorn [mailto:[EMAIL PROTECTED] Sent: 26 July 2004 12:18 To: [EMAIL PROTECTED] Subject: Debugging Queries Hi, I am using MySQL and OJB and now I want to create a Query over a large table. For performance reason I want to use the pageing-feature - but I have the feeling that currently OJB is somehow ommitting this (the result is fine - but the SQL seems not to include the LIMIT-clause). Is there a way to get the native SQL from a query which OJB would send to the database (this would help for other, complex queries too). With regards Tino - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] ___ HPD Software Ltd. - Helping Business Finance Business Email terms and conditions: www.hpdsoftware.com/disclaimer - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
hi tino, ojb does not use the limit-clause yet. the paging is implemented by positioning the cursor in the resultset. jakob Tino Schöllhorn schrieb: Hi, I am using MySQL and OJB and now I want to create a Query over a large table. For performance reason I want to use the pageing-feature - but I have the feeling that currently OJB is somehow ommitting this (the result is fine - but the SQL seems not to include the LIMIT-clause). Is there a way to get the native SQL from a query which OJB would send to the database (this would help for other, complex queries too). With regards Tino - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
Tino Schöllhorn wrote: I am using MySQL and OJB and now I want to create a Query over a large table. For performance reason I want to use the pageing-feature - but I have the feeling that currently OJB is somehow ommitting this (the result is fine - but the SQL seems not to include the LIMIT-clause). Is there a way to get the native SQL from a query which OJB would send to the database (this would help for other, complex queries too). A database specific way would be to add the line: log=/path/to/some/file.log to my.cnf, which would cause MySQL to write each and every query it receives out to file.log. You can then just monitor what goes in there. Unfortunately, there is a large performance penalty, but it can be handy for debugging whole transactions. -- Craig - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
Hi Jakob, thanks for your answer. Will that feature be implemented in OJB 1.1? We have some queries where that feature is important for us. If this is just a matter of the MySQLPlatform-Implementation I could help outor is this a general problem? With regards Tino Jakob Braeuchi wrote: hi tino, ojb does not use the limit-clause yet. the paging is implemented by positioning the cursor in the resultset. jakob Tino Schöllhorn schrieb: Hi, I am using MySQL and OJB and now I want to create a Query over a large table. For performance reason I want to use the pageing-feature - but I have the feeling that currently OJB is somehow ommitting this (the result is fine - but the SQL seems not to include the LIMIT-clause). Is there a way to get the native SQL from a query which OJB would send to the database (this would help for other, complex queries too). With regards Tino - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
hi tino, i do have an implementation using limit, but i think it's not finished yet. jakob Tino Schöllhorn schrieb: Hi Jakob, thanks for your answer. Will that feature be implemented in OJB 1.1? We have some queries where that feature is important for us. If this is just a matter of the MySQLPlatform-Implementation I could help outor is this a general problem? With regards Tino Jakob Braeuchi wrote: hi tino, ojb does not use the limit-clause yet. the paging is implemented by positioning the cursor in the resultset. jakob Tino Schöllhorn schrieb: Hi, I am using MySQL and OJB and now I want to create a Query over a large table. For performance reason I want to use the pageing-feature - but I have the feeling that currently OJB is somehow ommitting this (the result is fine - but the SQL seems not to include the LIMIT-clause). Is there a way to get the native SQL from a query which OJB would send to the database (this would help for other, complex queries too). With regards Tino - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
Jakob Braeuchi wrote: hi tino, i do have an implementation using limit, but i think it's not finished yet. Please be aware that not all databases support limits in sql (e.g. McKoi). Btw, do we use paging resultsets ? In that case, we might not need limits as the driver can optimize via cursors, or not ? Tom - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Debugging Queries
Hi Thomas, I am perfectly aware of that - but in my opinion you're already doing the right thing: emulate the behaviour of paging when the underlying db isn't supporting it. But if the underlying db is supporting this feature (many db implement this: mysql, mssql, oracle...) it should be used because one can have dramatically network and performance increases. With regards Tino Thomas Dudziak wrote: Jakob Braeuchi wrote: hi tino, i do have an implementation using limit, but i think it's not finished yet. Please be aware that not all databases support limits in sql (e.g. McKoi). Btw, do we use paging resultsets ? In that case, we might not need limits as the driver can optimize via cursors, or not ? Tom - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
