>>>>> "Ali" == Ali Akbar <the.ap...@gmail.com> writes:
Ali> I think yes, it will be good. The alternative is restructuring
Ali> this paragraph in the SRF docs:
>> The memory context that is current when the SRF is called is a
>> transient context that will be cleared between calls. This means
>> that you do not need to call pfree on everything you allocated
>> using palloc; it will go away anyway. However, if you want to
>> allocate any data structures to live across calls, you need to put
>> them somewhere else. The memory context referenced by
>> multi_call_memory_ctx is a suitable location for any data that
>> needs to survive until the SRF is finished running. In most cases,
>> this means that you should switch into multi_call_memory_ctx while
>> doing the first-call setup.
Ali> The important part "However, if you want to allocate any data
Ali> structures to live across calls, you need to put them somewhere
Ali> else." is buried in the docs.
Ali> But i think explicit warning is more noticeable for new
Ali> developer like me.
I was thinking something like this, added just after that para:
<warning>
<para>
While the actual arguments to the function remain unchanged between
calls, if you detoast the argument values (which is normally done
transparently by the
<function>PG_GETARG_<replaceable>xxx</replaceable></function> macro)
in the transient context then the detoasted copies will be freed on
each cycle. Accordingly, if you keep references to such values in
your <structfield>user_fctx</>, you must either copy them into the
<structfield>multi_call_memory_ctx</> after detoasting, or ensure
that you detoast the values only in that context.
</para>
</warning>
--
Andrew (irc:RhodiumToad)
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