This script will return true or false after testing that a userid is in a given role or is superuser

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

CREATE procedure [dbo].[_LIS_HasRole]

    @UserID int 
    ,@RoleName nvarchar(150) 

AS

    DECLARE @CheckUserID int
    DECLARE @HitCount int = 0

    SET @CheckUserID = @UserID
    IF @CheckUserID <> 0 
    BEGIN
    --if user is superuser
    SET @HitCount = (SELECT IsSuperUser FROM Users WHERE UserID = @CheckUserID)

     -- if user is administrator
    SET @HitCount = @HitCount + (
    SELECT COUNT(*)
    FROM UserRoles INNER JOIN
    Roles ON UserRoles.RoleID = Roles.RoleID INNER JOIN
    Users ON UserRoles.UserID = Users.UserID
    WHERE Roles.Rolename = 'Administrators' AND Users.UserID = @CheckUserID)

    --is user in the queried role
    SET @HitCount = @HitCount + (
    SELECT COUNT(*)
    FROM UserRoles INNER JOIN
    Roles ON UserRoles.RoleID = Roles.RoleID INNER JOIN
    Users ON UserRoles.UserID = Users.UserID
    WHERE Roles.Rolename = @RoleName AND Users.UserID = @CheckUserID)

--return the answer

    SELECT CAST(CASE WHEN @HitCount > 0 THEN 'True' ELSE 'False' END AS nvarchar(10)) AS HasRole
END
ELSE
    SELECT 'False' AS HasRole

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Or if you need to make this determination without a stored procedure

   Two other ways to do this with SQL are in the article read more