EMPTY()
Description
Checks whether the input string is empty. A string is considered non-empty if it contains at least one byte, even if this is a space or a null byte.
Syntax
> EMPTY(str)
Arguments
Arguments | Description |
---|---|
str | Required. both CHAR and VARCHAR are supported. |
Returned Values
Returns 1 for an empty string or 0 for a non-empty string.
Examples
> drop table if exists t1;
> create table t1(a varchar(255),b varchar(255));
> insert into t1 values('', 'abcd');
> insert into t1 values('1111', '');
> select empty(a),empty(b) from t1;
+----------+----------+
| empty(a) | empty(b) |
+----------+----------+
| 1 | 0 |
| 0 | 1 |
+----------+----------+