On 15/03/2022 14:07, Dmitry Yemanov wrote: > 15.03.2022 17:14, Adriano dos Santos Fernandes wrote: >> >> As part of "Support multiple rows for DML RETURNING (#6815)" feature, >> BLR verbs for "local table" were created. >> >> Local tables (LT) as defined there works outside transaction control. >> For #6815 this does not matter, but I want to add LT feature that will >> use these verbs. >> >> LTs are defined inside PSQL routines and its data is separated per >> routine invocation. For example a recursive routine will have different >> data in its LTs per each invocation, like local variables. > > What about autonomous transactions? Will procedure's LT data be visible > for them or every autonomous transaction gets its own copy? >
Like a standard variable, data will be shared with the autonomous transaction scope. Note that if we say that as the contrary, LT would be very similar to a LTT (with transaction control). And that would not be problematic, but... I also want packaged LT in the future, with would be very useful to work outside transaction control. >> SQL standard defines LOCAL TEMPORARY TABLES (LTT), which may be >> "created" or "declared". The semantics of these standard specs are >> different and not very easy applicable to Firebird as they are based on >> standard notion of modules, that is not similar to PSQL routines. > > I'd just adapt their definitions to our realities. For me, "created" LTT > is similar to GTT (i.e. stored in the schema) but with data isolated per > request (per PSQL routine). My understanding is that it is per session / package (SQL-client module), not request / routine. > "Declared" LTTs are defined inside the PSQL routine, Inside a package (SQL-client module) with data shared in the package / session. > In fact, what you priorly define as LT is IMO "declared" LTT. > I had that impression before read the standard, but then I changed my opinion. I also did not found any major DBMS that implemented declared LTTs, nor SQL-standard modules. Adriano Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
