SQL查询，用于从多个表中查找具有表名的所有记录

Question

I have three table Table1,Table2,Table3. Each table contains Column "Comments". So i want to find the records with table name.

For Example:

Table1

Id         Comments

98         test

99         test

100        attach

Table2

Id    Comments 

101   test

102   test

103   module

Table3

Id    Comments

111   test

112   test

113   exist

If i say select * from Table1,Table2,Table3 where comments like '%test%'

Result should be like this :

Id      Table    Comments

98      Table1   test

99      Table1   test

101     Table2   test

102     Table2   test

111     Table3   test

112     Table3   test

Answer 1

You could use a UNION query:

SELECT Id, 'Table1' AS Table, Comments
FROM Table1
WHERE Comments LIKE '%test%'
UNION ALL
SELECT Id, 'Table2' AS Table, Comments
FROM Table2
WHERE Comments LIKE '%test%'
UNION ALL
SELECT Id, 'Table3' AS Table, Comments
FROM Table3
WHERE Comments LIKE '%test%`