Doubt in heap_release_fetch - Mailing list pgsql-hackers

Hello,<br /><br />What do the following lines mean :<br /><br />  /* Tuple failed time qual, but maybe caller wants to
seeit anyway. */<br />        if (keep_buf)<br />                *userbuf = buffer;<br />        else<br />        {<br
/>               ReleaseBuffer(buffer);<br />                *userbuf = InvalidBuffer;<br />        }<br /><br />What
isthe time qualification check ?<br /><br />Thanks,<br />Suresh<br /><br /><br /><p><hr size="1" />Never miss a thing.
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