Function MakeSimpleIdExpr

pg_documentdb/src/query/query_operator.c:3890–3909

* Creates a basic object_id op_expr for a given collection var. */

 * Creates a basic object_id <op> <value> op_expr for a given collection var.
 */
Expr *
MakeSimpleIdExpr(const bson_value_t *filterValue, Index collectionVarno, Oid operatorId)
{
	pgbson *qualValue = BsonValueToDocumentPgbson(filterValue);
	Const *documentIdConst = makeConst(BsonTypeId(), -1, InvalidOid, -1,
									   PointerGetDatum(qualValue),
									   false, false);

	/* _id is always the second column in our data tables */
	AttrNumber documentIdAttnum = 2;
	Var *documentIdVar = makeVar(collectionVarno, documentIdAttnum, BsonTypeId(), -1,
								 InvalidOid, 0);

	/* construct object_id <operator> <value> expression */
	Expr *documentIdFilter = make_opclause(operatorId, BOOLOID, false,
										   (Expr *) documentIdVar,
										   (Expr *) documentIdConst, InvalidOid,
										   InvalidOid);
	return documentIdFilter;
}


Expr *