isnull
Description
Checks whether the value is NULL
, returns 1
if it is NULL
, and returns 0
if it is not NULL
.
Syntax
ISNULL(v)
Parameters
v
: the value to check. All date types is supported.
Return value
Returns 1 if it is NULL
, and returns 0 if it is not NULL
.
Example
MYSQL > SELECT c1, isnull(c1) FROM t1;
+------+--------------+
| c1 | `c1` IS NULL |
+------+--------------+
| NULL | 1 |
| 1 | 0 |
+------+--------------+