DECLARE @total INT
DECLARE @count INT
DECLARE @name NVARCHAR(25)
DECLARE @rn INT

SET @total = (SELECT COUNT(Name) FROM sys.tables)
SET @count = 1
SET @rn = (SELECT ROW_NUMBER() OVER(ORDER BY Name) FROM sys.tables)



WHILE @count <= @total AND @count < 2
    BEGIN
        SET @name = (   SELECT Name, ROW_NUMBER() OVER(ORDER BY Name)
                        FROM sys.tables
                        WHERE @rn = @count
                     )

        EXEC('SELECT * FROM WS_Live.dbo.' + @name + ' WHERE GCRecord IS NOT NULL')
        SET @count += 1

    END

Msg 116, Level 16, State 1, Line 19
Only one expression can be specified in the select list when the subquery is not introduced with EXISTS.