Home / Tricky Select Queries / Question No: 53

I want to use a select statement to retrieve multiple records without a reference table. Obviously it is easy to retrieve a single record is simple enough:

SELECT 'val_1' AS var1, 'val_2' AS var2;

+--------+--------+
| var1   | var2 |
+--------+--------+
| val_1 | val_2 |
+--------+--------+

But I need to produce multiple records without referencing any tables:

+--------+--------+
| var1   | var2   |
+--------+--------+
| val_1 | val_2 |
| val_3 | val_4 |
| val_5 | val_6 |
+--------+--------+

To retrieve multiple records without a reference table, you can use UNION operator provided by MySQL. It may serve your goal.  Take an example:

SELECT  'val_1' AS var1,  'val_2' AS var2 
UNION 
SELECT  'val_3' AS var1,  'val_4' AS var2 
UNION 
SELECT  'val_5' AS var1,  'val_6' AS var2;