REQUEST_ID = CAST('%%' AS VARCHAR)

convert(VARCHAR(50),REQUEST_ID )= convert(VARCHAR(50),value)

Perform a Casting from BigInt To Varchar

Declare @REQUEST_ID AS BIGINT = 1234

SELECT Result = CASE WHEN CAST(@REQUEST_ID AS VARCHAR) = CAST('1234' AS VARCHAR) THEN 1 ELSE 0 END

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