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

然而，这不起作用。无论如何在MySQL的一个查询中实现这一点？感谢。

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

Answer 2

每个FROM都需要单独的WHERE和SELECT子句，但UNION或UNION ALL可以使用。{/ p>

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

Answer 3

是UNION ALL

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

UNION ALL

SELECT post_id, 'custom', custom
FROM `wp_temp`
WHERE custom IS NOT NULL

如何使用INSERT INTO多次选择插入？

3 个答案: