Character Auto Increment in Mysql?.

AS
BEGIN
BEGIN TRANSACTION
    IF NOT EXISTS (SELECT 1 FROM Item_Master where Item_Code = @Item_Code)
    BEGIN
    DECLARE @ItemCode VARCHAR(10)
    SET @ItemCode =(SELECT RIGHT(MAX(CONVERT(VARCHAR(8),Item_Code)),6) +1 FROM Item_Master)
    IF(@ItemCode IS NULL)
    BEGIN
    SET @ItemCode = '000001'
    end
    ELSE
    BEGIN
        if LEN(@ItemCode) = 1
        BEGIN
            set @ItemCode = '00000' + @ItemCode
        end
        else if LEN(@ItemCode) = 2
        BEGIN
            set @ItemCode = '0000' + @ItemCode
        end
        else if LEN(@ItemCode) = 3
        BEGIN
            set @ItemCode = '000' + @ItemCode
        end
        else if LEN(@ItemCode) = 4
        BEGIN
            set @ItemCode = '00' + @ItemCode
        end
        else if LEN(@ItemCode) = 5
        BEGIN
            set @ItemCode = '0' + @ItemCode
        end
        else if LEN(@ItemCode) = 6
        BEGIN
            set @ItemCode = @ItemCode
        end
    end