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IF

If expr1 is TRUE, IF() returns expr2. Otherwise, it returns expr3.

Syntax​

IF( <expr1>, <expr2>, <expr3>)

Arguments​

ArgumentsDescription
<expr1>The condition for evaluation that can be true or false.
<expr2>The expression to return if condition is met.
<expr3>The expression to return if condition is not met.

Return Type​

The return type is determined by expr2 and expr3, they must have the lowest common type.

Examples​

SELECT if(number=0, true, false) FROM numbers(1);
+-------------------------------+
| if((number = 0), true, false) |
+-------------------------------+
|                             1 |
+-------------------------------+
SELECT if(number > 5, number*5, number+5 ) FROM numbers(10);
+----------------------------------------------+
| if((number > 5), (number * 5), (number + 5)) |
+----------------------------------------------+
|                                            5 |
|                                            6 |
|                                            7 |
|                                            8 |
|                                            9 |
|                                           10 |
|                                           30 |
|                                           35 |
|                                           40 |
|                                           45 |
+----------------------------------------------+