Question

I want to use a variable value in exec where i don’t need to create the query itself.
I will have a query stored in a field in my database and i just want to execute that using the parameters in that stored procedure. For Example below i declared two variables @ValueVariable is the parameter of stored procedure and what i declared @QueryString is the one i will read from data base and i want to execute that using the value of @ValueVariable.

DECLARE @ValueVariable  int=0
        @QueryString    VARCHAR(MAX)=
                        'SELECT UserName FROM TableUser WHERE UserId=@ValueVariable'

EXEC(@QueryString)

When i try to execute that i get an error Incorrect syntax near ‘SELECT UserName FROM TableUser WHERE UserId=@ValueVariable’

I am aware that i can do it by

@QueryString    VARCHAR(MAX)=
                            'SELECT UserName FROM TableUser WHERE UserId='+@ValueVariable

But i want to use it as stated above. Not making a query in my procedure but using variable value as in string retrieved from DB.

So is there any way i could be able to execute that using the value from the variable in current environment.

Answer 1

You can use sp_executesql.

DECLARE
  @IntVariable    int,
  @SQLString      nvarchar(500),
  @ParmDefinition nvarchar(500)
SELECT
  @IntVariable    = 0,
  @SQLString      = N'SELECT UserName FROM TableUser WHERE UserId=@ValueVariable',
  @ParmDefinition = N'@ValueVariable INT'

SP_EXECUTESQL
  @SQLString,
  @ParmDefinition,
  @ValueVariable = @IntVariable;

In essence, it creates a one time stored procedure. The @paramDefinition variable is the parameter signature you’d normally see in a stored procedure, the sql server caches the execution plan, etc, etc.