我在 sqlite3 中创建此触发器 second_loop 时遇到问题:它是更多代码的一部分,但正是这部分给出了错误。当我在数据库上执行代码时,我得到以下信息:near "CREATE": syntax error。
我确信触发器内部的部分工作得很好,因为我已经单独测试过了,但是这肯定有其他类型的问题。
请注意,我在同一个 SQL 中有另一个触发器,它工作得很好!
请指教,谢谢
CREATE TRIGGER second_loop AFTER UPDATE OF stack_count ON global WHEN NEW.stack_count<>0
BEGIN
CREATE TEMP TABLE last_row(id INTEGER PRIMARY KEY, unvisited INTEGER DEFAULT 1, predecessor INTEGER DEFAULT 0, discovery INTEGER DEFAULT 0, finish INTEGER DEFAULT 0);
INSERT INTO last_row
SELECT *
FROM nodes
WHERE id = (SELECT node_id
FROM stack
ORDER BY oid DESC LIMIT 1);
UPDATE last_row SET unvisited =0, predecessor = (SELECT parent_id FROM global), discovery = (SELECT time FROM global);
UPDATE global SET current_id = (SELECT node_id FROM stack WHERE ROWID = (SELECT MAX(ROWID) FROM stack));
UPDATE global SET time = time + 1;
DELETE FROM stack WHERE ROWID = (SELECT MAX(ROWID));
INSERT INTO stack(node_id)
SELECT DISTINCT edges.target_id
FROM nodes, edges, global
WHERE edges.source_id=global.current_id AND nodes.unvisited=1;
-- update stack count to go to second_loop trigger
UPDATE global SET stack_count = stack_count + 1;
END;