<structfield>multi_call_memory_ctx</> while doing the first-call setup.

</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>

<para>

A complete pseudo-code example looks like the following:

<programlisting>