Lets say i have 4 identical tables: table1, table2, table3, table4
All table have same structure: id total开发者_StackOverflow date
I want to get all information from all tables using same condition. I mean merge 4 sql requests in 1
So instead of having these 4 sql, have just one. Remember, same condition for all tables, in our case date = 2011-06-23
SELECT * FROM table1 where date = '2011-06-23'
SELECT * FROM table2 where date = '2011-06-23'
SELECT * FROM table3 where date = '2011-06-23'
SELECT * FROM table4 where date = '2011-06-23'
Thank you for your time.
(SELECT * FROM table1 where date = '2011-06-23')
UNION
(SELECT * FROM table2 where date = '2011-06-23')
UNION
(SELECT * FROM table3 where date = '2011-06-23')
UNION
(SELECT * FROM table4 where date = '2011-06-23')
UNION is what you are looking for
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