Support MULTISET functionality
------------------------------
Key: CORE-5276
URL: http://tracker.firebirdsql.org/browse/CORE-5276
Project: Firebird Core
Issue Type: New Feature
Reporter: Vladimir Arkhipov
I think there are many useful ways to use MULTISET's (according to SQL:2003
standard) but for me the main advantage is ability to use it in PLSQL for IN
statement.
At present if we need to pass filter parameter consisting of several elements
(for example FIELD IN (1, 3)) we should use sql concatenation instead of
parameters.
At first, this is not convenient to write EXECUTE STATEMENT 'SQL_TEXT' instead
of "explicit" PLSQL SELECT with parameters each time when you need to use
simple IN condition.
At second, if I understand correctly, it is not good for performance because
statement have to be prepared each time with different parameter values.
P.S. I understand that I can use condition like "FIELD IN (select id from
get_id_from_str(:text))" (we use this approach too), but as I understand, in
this case index is not used, result of procedure is not cached and procedure
will be called for each record. May be some optimizations in this direction can
help, but MULTISET will be useful anyway.
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://tracker.firebirdsql.org/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira
------------------------------------------------------------------------------
What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic
patterns at an interface-level. Reveals which users, apps, and protocols are
consuming the most bandwidth. Provides multi-vendor support for NetFlow,
J-Flow, sFlow and other flows. Make informed decisions using capacity
planning reports. https://ad.doubleclick.net/ddm/clk/305295220;132659582;e
Firebird-Devel mailing list, web interface at
https://lists.sourceforge.net/lists/listinfo/firebird-devel
