SQL - TRY_CAST() Function

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The SQL TRY_CAST() function is one of the Conversions functions in SQL, which is similar to the CAST Function. It is applied to the transformation of expressions between various data types. It is employed to change an expression's data type. If it is successful, SQL TRY CAST will return the expression in the chosen data type. It will return null if not.

The way unsuccessful casts are handled is the primary distinction between the TRY CAST() and CAST() functions. The CAST() function produces an error for failing cast operations, whereas TRY CAST() returns a NULL.

Syntax

Following is the syntax of the SQL TRY_CAST() function −

TRY_CAST ( expression AS data_type [ ( length ) ] )  

Parameters

This function accepts only three parameter. The same is described below −

• expression − the valid expression that to be cast.

• datatype − It is the datatype that we want to cast the expression to.

• length − It was used to define the length of any targeted data type, as it was an optional parameter of an integer type.

Example

Let us try to cast the string to decimal with TRY_CAST() function by using the following query −

SELECT TRY_CAST('123.45' AS DECIMAL(6, 2)) Result;

Output

When we execute the above query, the output is obtained as follows −

+------------------------------------+
|                              Result|
+------------------------------------+
|                             123.45 |
+------------------------------------+

Example

In the following example we are going to using the GETDATE() along with TRY_CAST() function to convert date and time to the date value by using the following query −

SELECT TRY_CAST(GETDATE() AS DATE) Result;

Output

On executing the above query, the output is displayed as follows −

+------------------------------------+
|                              Result|
+------------------------------------+
|                          2023-02-23|
+------------------------------------+

Example

Considering the following example, where we are going to use the GETDATE() along with TRY_CAST() function to convert expression into varchar by using the following query −

SELECT TRY_CAST(GETDATE() AS VARCHAR(22)) AS Result;

Output

On executing the above query, the output is displayed as follows −

+------------------------------------+
|                              Result|
+------------------------------------+
|                Feb 23 2023 12:17PM |
+------------------------------------+

Example

Let's look into the another scenario, where we are going to using the GETDATE() along with TRY_CAST() function to convert date and time to the time value by using the following query −

SELECT TRY_CAST(GETDATE() AS TIME) Result;

Output

The output for the above query is produced as given below −

+------------------------------------+
|                              Result|
+------------------------------------+
|                   11:57:20.3266667 |
+------------------------------------+

Example

Look at the following example, where we are going to convert the decimal value to the int by using the following query −

SELECT TRY_CAST(112233.4455 AS int) AS Result;

Output

If we compile and run the above query, the result is produced as follows −

+------------------------------------+
|                              Result|
+------------------------------------+
|                             112233 |
+------------------------------------+

Example

let's look into the following example, where TRY_CAST() function returning NULL when it doesn't gets exceeded by using the following query −

SELECT TRY_CAST('TUTORIALSPOINT' AS int) AS Result;

Output

On executing the above query, it will generate the following output as shown below −

+------------------------------------+
|                              Result|
+------------------------------------+
|                               NULL |
+------------------------------------+

Example

Let’s consider another example, where we are going to use the TRY_CAST()function with case and running the following query −

SELECT 
CASE WHEN TRY_CAST('TUTORIALSPOINT' AS int) IS NULL
 THEN 'CastFailed'  
    ELSE 'CastSucceeded'  
END AS Result;

Output

When the query gets executed, it will generate the output as shown below −

+------------------------------------+
|                              Result|
+------------------------------------+
|                         CastFailed |
+------------------------------------+

Example

considering the following the following example, where we are casting the expression to the money by using the following query −

DECLARE @STR AS VARCHAR(22)
SET @STR = '12345'
SELECT TRY_CAST(@STR AS MONEY) AS Result; 

Output

When we execute the above query, the output is obtained as follows −

+------------------------------------+
|                              Result|
+------------------------------------+
|                           12345.00 |
+------------------------------------+