如何使用INSERT INTO多次选择插入？

Question

我试图为表中的每个字段插入两个数据,如下所示:

INSERT INTO `wp_postmeta` (post_id, meta_key, meta_value)
SELECT post_id, 'custom', custom
SELECT post_id, '_custom', 'field_514e91e73640d'
FROM `wp_temp`
WHERE custom IS NOT NULL

但是,这不起作用.无论如何在MySQL的一个查询中实现这一点？谢谢.

Answer 1

INSERT INTO `wp_postmeta` (post_id, meta_key, meta_value)
SELECT post_id, 'custom', custom FROM `wp_temp` WHERE custom IS NOT NULL
UNION ALL
SELECT post_id, '_custom', 'field_514e91e73640d' FROM `wp_temp` WHERE custom IS NOT NULL