The conceptual difference is rather simple: - A QueryPart is a concrete object in the query's AST and can be replaced directly by another QueryPart. - A clause is a more syntactic idea of something that groups several QueryParts. Clauses don't have formal equivalents in the AST.
An example of a clause is SELECT_FROM. It clearly delimits the FROM clause within a SELECT statement. Having clauses in the VisitContext allows you to distinguish between the different locations where a Table QueryPart is referenced from, e.g. the FROM clause, or the SELECT clause (as part of a Field). Does this make sense? We might improve this situation in jOOQ 4.0 and model all "clauses" as proper QueryParts, removing the need for these synthetic objects. 2014-09-24 18:15 GMT+02:00 <[email protected]>: > Hi Lukas, > > Ok, that's good ! > I am just starting using VisitListener, for the moment my code is nearly > the same as your test unit. > > I have a more general question for my understanding about VisitListener, > what's the difference between visitStart and ClauseStart ? > > Javadoc says that VisitStart is called just before visiting a QueryPart > and the other just before entering a Clause. > A queryPart seems to have many clauses. Please, could you give me an > exemple ? > > Thanks for your help. > > Cheers > > Alex > > Le mercredi 24 septembre 2014 17:21:04 UTC+2, Lukas Eder a écrit : >> >> Hi Alex, >> >> Thanks for linking that. I keep forgetting that this test is part of the >> test suite :-) We should be moving that into a new downloadable example >> project, where this use-case and many more can be debugged through for >> better understanding. >> >> Again, thanks for your info and glad it worked out for you. >> >> If you have any further questions / issues with the VisitListener, let us >> know >> >> Cheers >> Lukas >> >> 2014-09-24 17:07 GMT+02:00 <[email protected]>: >> >> Hi Lukas, >>> >>> Yes, of course ! >>> >>> My main need was to add automatically some fields into the where clause >>> (like multi tenant discriminator). >>> >>> This unit test help me a lot. It is more complex than the documentation >>> example, but according to me, it is really more useful ! >>> >>> https://github.com/jOOQ/jOOQ/blob/af7a7c504c08fcd4ecb10c9ca4091a >>> 7cff930fb8/jOOQ-test/src/test/java/org/jooq/test/all/ >>> testcases/VisitListenerTests.java >>> >>> Cheers, >>> >>> Alex >>> >>> Le mercredi 24 septembre 2014 16:59:18 UTC+2, Lukas Eder a écrit : >>>> >>>> Hi Alexandre, >>>> >>>> That's great! Would you mind showing us a little what you did? I think >>>> this could be very valuable for future visitors of this mailing list >>>> thread. >>>> >>>> Cheers, >>>> Lukas >>>> >>>> 2014-09-24 16:29 GMT+02:00 <[email protected]>: >>>> >>>> Hello Lukas, >>>>> >>>>> OK, thanks for your answer, I have finally solved my problem with >>>>> Visitor SPI ! >>>>> >>>>> Le mercredi 24 septembre 2014 15:49:55 UTC+2, Lukas Eder a écrit : >>>>>> >>>>>> Yes, ExecuteListener is good for hooking into the lifecycle of >>>>>> rendering the SQL string, passing it to a JDBC PreparedStatement, passing >>>>>> the bind values to the PreparedStatement, executing the statement and >>>>>> fetching the results - whereas VisitListener allows for more detailed >>>>>> interaction with the SQL rendering and bind variable extraction steps. >>>>>> >>>>>> 2014-09-24 10:57 GMT+02:00 <[email protected]>: >>>>>> >>>>>>> I have implemented an ExecuteListener but VisitListener permit to do >>>>>>> SQL transformation, I will check this one ! >>>>>>> >>>>>>> Le mercredi 24 septembre 2014 10:27:24 UTC+2, [email protected] >>>>>>> a écrit : >>>>>>> >>>>>>>> Hello, >>>>>>>> >>>>>>>> I am evatuating your library for maybe use it in our new project. >>>>>>>> I have implemented my own listener and I want to check somes >>>>>>>> conditions into the query (where clause). Or maybe add a condition to >>>>>>>> the >>>>>>>> query. >>>>>>>> >>>>>>>> Is there a way to access to the private attribute conditions into >>>>>>>> the query object ? It seems to be very interesting for doing this. >>>>>>>> >>>>>>>> The only solution I have found is to use >>>>>>>> ctx.query().getSQL(ParamType.INLINED) but it is more complicated >>>>>>>> to work with a String. >>>>>>>> >>>>>>>> Thanks for your help. >>>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "jOOQ User Group" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>> >>>>>> >>>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "jOOQ User Group" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "jOOQ User Group" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "jOOQ User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "jOOQ User Group" group. 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