Function CallUpdateWorker

pg_documentdb/src/commands/update.c:2290–2350

static Datum
CallUpdateWorker(MongoCollection *collection, pgbson *serializedSpec,
				 pgbsonsequence *updateDocs, int64 shardKeyHash, text *transactionId)
{
	int argCount = 6;
	Datum argValues[6];

	/* whitespace means not null, n means null */
	char argNulls[6] = { ' ', ' ', ' ', ' ', 'n', 'n' };
	Oid argTypes[6] = { INT8OID, INT8OID, REGCLASSOID, BYTEAOID, BYTEAOID, TEXTOID };

	const char *updateQuery = FormatSqlQuery(
		" SELECT %s.update_worker($1, $2, $3, $4::%s.bson, $5::%s.bsonsequence, $6) FROM %s.documents_"
		UINT64_FORMAT " WHERE shard_key_value = %ld",
		DocumentDBApiInternalSchemaName, CoreSchemaNameV2, CoreSchemaNameV2,
		ApiDataSchemaName, collection->collectionId,
		shardKeyHash);

	argValues[0] = UInt64GetDatum(collection->collectionId);

	/* p_shard_key_value */
	argValues[1] = Int64GetDatum(shardKeyHash);

	/* p_shard_oid: We set this to InvalidOid here. The planner hook on the worker node will set this to
	 * non-InvalidOid before the actual function is executed.
	 */
	argValues[2] = ObjectIdGetDatum(InvalidOid);
	argValues[3] = PointerGetDatum(serializedSpec);

	if (updateDocs != NULL)
	{
		argValues[4] = PointerGetDatum(updateDocs);
		argNulls[4] = ' ';
	}

	if (transactionId != NULL)
	{
		argValues[5] = PointerGetDatum(transactionId);
		argNulls[5] = ' ';
	}

	bool readOnly = false;

	Datum resultDatum[1] = { 0 };
	bool isNulls[1] = { false };
	int numResults = 1;

	/* forceDelegation assumes nested distribution */
	RunMultiValueQueryWithNestedDistribution(updateQuery, argCount, argTypes, argValues,
											 argNulls,
											 readOnly, SPI_OK_SELECT, resultDatum,
											 isNulls, numResults);

	if (isNulls[0])
	{
		ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_INTERNALERROR),
						errmsg("update_worker should not return null")));
	}