Function ExecHashJoinSaveTuple

src/backend/executor/nodeHashjoin.c:1565–1610

* ExecHashJoinSaveTuple * save a tuple to a batch file. * * The data recorded in the file for each tuple is its hash value, * then the tuple in MinimalTuple format. * * Note: it is important always to call this in the regular executor * context, not in a shorter-lived context; else the temp file buffers * will get messed up. */

 * will get messed up.
 */
void
ExecHashJoinSaveTuple(PlanState *ps, MinimalTuple tuple, uint32 hashvalue,
					  HashJoinTable hashtable, BufFile **fileptr,
					  MemoryContext bfCxt)
{
	BufFile    *file = *fileptr;

	if (hashtable->work_set == NULL)
	{
		/*
		 * First time spilling.
		 */
		if (hashtable->hjstate->js.ps.instrument)
		{
			hashtable->hjstate->js.ps.instrument->workfileCreated = true;
		}

		MemoryContext oldcxt;

		oldcxt = MemoryContextSwitchTo(bfCxt);
		hashtable->work_set = workfile_mgr_create_set("HashJoin", NULL, true /* hold pin */);
		MemoryContextSwitchTo(oldcxt);
	}

	if (file == NULL)
	{
		MemoryContext oldcxt;

		oldcxt = MemoryContextSwitchTo(bfCxt);

		/* First write to this batch file, so create it */
		Assert(hashtable->work_set != NULL);
		file = BufFileCreateTempInSet("HashJoin", false /* interXact */,
									  hashtable->work_set);
		BufFilePledgeSequential(file);	/* allow compression */
		*fileptr = file;

		elog(gp_workfile_caching_loglevel, "create batch file %s",
			 BufFileGetFilename(file));

		MemoryContextSwitchTo(oldcxt);
	}

	BufFileWrite(file, (void *) &hashvalue, sizeof(uint32));
	BufFileWrite(file, (void *) tuple, tuple->t_len);
}

/*
 * ExecHashJoinGetSavedTuple