mysql - 如果 MySQL 中的表中不存在则插入记录失败

Question

这是我的查询:

INSERT INTO table (id, actions, date, comments, type, url, rating)
  SELECT * FROM (SELECT 'b7d54d99bf11', 'Information Exchanged', '1430463600', '', 'routine', 'http://example.com', '') AS tmp
    WHERE NOT EXISTS (SELECT url FROM table WHERE url = 'http://example.com')

我收到一条 SQL 错误，显示重复列名:''，因为某些记录没有传入评级或注释。

如何避免该错误？有没有更好的方法来实现这一目标？

Answer 1

您必须包含列的别名

INSERT INTO table (id, actions, date, comments, type, url, rating)
  SELECT * FROM (SELECT 'b7d54d99bf11' as id, 
                        'Information Exchanged' as actions, 
                        '1430463600' as date, 
                        '' as comments, 
                        'routine' as type, 
                        'http://example.com' as url, 
                        '' as rating) AS tmp