ISJSON (Transact-SQL)

THIS TOPIC APPLIES TO: yesSQL Server (starting with 2016)yesAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse

Tests whether a string contains valid JSON.

Topic link icon Transact-SQL Syntax Conventions

Syntax

ISJSON ( expression )  

Arguments

expression
The string to test.

Return Value

Returns 1 if the string contains valid JSON; otherwise, returns 0. Returns null if expression is null.

Does not return errors.

Remarks

ISJSON does not check the uniqueness of keys at the same level.

Examples

Example 1

The following example runs a statement block conditionally if the parameter value contains valid JSON.

DECLARE @param <data type>
SET @param = <value>

IF (ISJSON(@param) > 0)  
BEGIN  
     -- Do something with the valid JSON value of @param.  
END

Example 2

The following example returns the JSON text if the column contains valid JSON.

SELECT id,json_col
FROM tab1
WHERE ISJSON(json_col)>0 

See Also

JSON Data (SQL Server)