I'm creating a view that is using data that comes from the same table twice. As a result, same column names appear twice.
Thus, i need to give aliases to these columns. If i were to do it, i'd write it as:
SELECT u.* as 'one_*', u2.* as 'two_*'
FROM users u
LEFT JOIN relationships r ON u.id=r.id_one
LEFT JOIN users u2 ON r.id_two=u2.id
But that doesn't work. Thanks for your help!
EDIT:
Here's the data i'm actually getting:
| id | name | id | name |
1 john 2 alex
Here's the data i'd like to get (while still using a SELECT u.*, u2.*):
| id | name | brother_id | brother_name |
1 john 2 alex
You can't use * with an alias. Aliases can be used for individual columns.
You'll have to alias each column instead..
So unfortunately, if you have a lot of columns, you'll need to go:
SELECT u.col1 AS u_col1
, u.col2 AS u_col2
, u.col3 AS u_col3
-- etc
, u2.col1 AS u2_col1
, u2.col2 AS u2_col2
, u2.col3 AS u2_col3
-- etc
FROM table1 AS u
-- INNER JOIN / LEFT OR RIGHT OUTER JOIN / ,
table2 AS u2
Try using a UNION query:
e.g.
select a.typeid, a.typename from MYTABLE a where a.typeid=3 UNION select a.typeid, a.typename from MYTABLE a where a.typeid=4
Can you not just use SELECT * and then in your code refer to u.field1 and u2.field2?
SELECT alias.* does certainly work in mysql >= 5.6
来源:https://stackoverflow.com/questions/8341136/mysql-alias-for-select-columns