这个存储过程如何改成 MySql写法

[nitaiyoucala]

CREATE PROCEDURE [dbo].[Pro_Pager]
        @PageSize NVARCHAR(20),
        @RowStart nvarchar(20),
        @SQLStr nvarchar(max),
        @Orderby nvarchar(100)
AS
BEGIN
 DECLARE @StrSQL  NVARCHAR(max)
 SET @StrSQL=' SELECT TOP '+@PageSize+' * FROM ( SELECT   ROW_NUMBER() OVER (ORDER BY '+@Orderby+') AS NUMBER ,*  FROM ('+@SQLStr+')AS TableA )  AS TableB WHERE TableB.NUMBER>'+@RowStart+''
 DECLARE @StrCountSQL  NVARCHAR(max)
 SET @StrCountSQL='SELECT COUNT(*) FROM ('+@SQLStr+') AS TableC'
EXEC (@StrSQL+@StrCountSQL)

END