MS Access IsDate() Function

The IsDate() function in MS Access checks whether a given expression can be interpreted as a valid date. This is a very useful function for data validation, particularly when dealing with data that might contain invalid date formats or non-date values.

IsDate(): Definition and Usage

IsDate() is used to determine if a value can be converted to a date data type. It's often used to ensure that data entered into a date field conforms to the correct format and to prevent errors caused by invalid dates. The function returns a Boolean value: True (-1) if the expression is a valid date and False (0) otherwise.

Syntax

IsDate(expression)
      

Parameter Values

Examples

Testing the Current Date

This example checks if the current date (returned by the Now() function) is a valid date—it should be!

SELECT IsDate(Now());
      

True (-1)
      

Testing Invalid Date Text

This checks if the text string "Hello" can be interpreted as a date (it cannot).

SELECT IsDate("Hello");
      

False (0)
      

Testing a Valid Date String

This checks a date string in a common format.

SELECT IsDate("August 25, 2017");
      

True (-1)
      

Testing a Date Literal

Checking a date using Access's date literal notation.

SELECT IsDate(#25/8/2017#);
      

True (-1)