T-SQL ISDATE() Function

The T-SQL (Transact-SQL) ISDATE() function returns 1 if the expression is a valid datetime value. Otherwise, it returns 0.

Syntax

ISDATE(expression)

Parameters

expression Required. Specify a character string or expression to check whether it is a date. It must be less than 4000 characters. Date and time data types, except datetime and smalldatetime, are not allowed as the argument for this function.

Return Value

Returns 1 if the expression is a valid datetime value, else returns 0.

Example 1:

The example below shows the usage of ISDATE() function.

SELECT ISDATE('2019-10-25');
Result: 1

SELECT ISDATE('2019-10-25 08:10:25');
Result: 1

SELECT ISDATE('2019-10-25 08:10:25.123');
Result: 1

SELECT ISDATE('08:10:25.123');
Result: 1

SELECT ISDATE('Hello World');
Result: 0

SELECT ISDATE(123);
Result: 0

SELECT ISDATE(NULL);
Result: 0

Example 2:

Consider a database table called Employee with the following records:

EmpID	Name	City	Age	Date_of_Joining
1	John	London	25	2018-05-25
2	Marry	New York	24	NULL
3	Jo	Paris	27	2019-06-09
4	Kim	Amsterdam	30	NULL
5	Ramesh	New Delhi	28	2019-10-25
6	Suresh	Mumbai	28	2021-12-26

The statement given below can be used to check if a record of Date_of_Joining column is a valid date or not.

SELECT *, ISDATE(Date_of_Joining) AS ISDATE_Value FROM Employee;

This will produce the result as shown below:

EmpID	Name	City	Age	Date_of_Joining	ISDATE_Value
1	John	London	25	2018-05-25	1
2	Marry	New York	24	NULL	0
3	Jo	Paris	27	2019-06-09	1
4	Kim	Amsterdam	30	NULL	0
5	Ramesh	New Delhi	28	2019-10-25	1
6	Suresh	Mumbai	28	2021-12-26	1

❮ T-SQL Functions