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我正在尝试从包含列“lang”和“project”的指定数据库中选择所有表。这就是我正在做的事情：

SELECT DISTINCT(ISC1.TABLE_NAME) AS `table` FROM INFORMATION_SCHEMA.COLUMNS AS ISC1 
JOIN INFORMATION_SCHEMA.COLUMNS AS ISC2 ON 
    (ISC1.TABLE_SCHEMA=ISC2.TABLE_SCHEMA AND ISC1.TABLE_NAME=ISC2.TABLE_NAME AND ISC2.COLUMN_NAME='project') 
WHERE ISC1.COLUMN_NAME='lang' AND ISC2.COLUMN_NAME='project' AND ISC1.TABLE_SCHEMA='some_database'
  • 它确实有效，但我觉得编写这种查询是一种不好的方式。如果有人可以改进它，那就太好了。
  • 现在我必须更改此查询以选择所有具有“lang”列但没有“project”列的表。老实说，我不知道从哪里开始......

谢谢你的帮助

4

1 回答 1

2 
SELECT DISTINCT(ISC1.TABLE_NAME) AS `table`
FROM INFORMATION_SCHEMA.COLUMNS AS ISC1,
    INFORMATION_SCHEMA.COLUMNS AS ISC2 
WHERE ISC1.TABLE_SCHEMA=ISC2.TABLE_SCHEMA
AND ISC1.TABLE_NAME=ISC2.TABLE_NAME
AND ISC2.COLUMN_NAME='project'
AND ISC1.COLUMN_NAME='lang'
AND ISC1.TABLE_SCHEMA='some_database'

没有项目栏：

SELECT DISTINCT(ISC.TABLE_NAME) AS `table`
FROM INFORMATION_SCHEMA.COLUMNS AS ISC
WHERE ISC.COLUMN_NAME='lang'
AND ISC.TABLE_SCHEMA='some_database'
AND NOT EXISTS(SELECT *
    FROM INFORMATION_SCHEMA.COLUMNS C
    WHERE C.COLUMN_NAME = 'project'
    AND C.TABLE_NAME=ISC.TABLE_NAME
    AND C.TABLE_SCHEMA=ISC.TABLE_SCHEMA)
于 2012-12-03T15:49:28.277 回答