SQL分页查询语句分析(二)
CHAR(3000)
DECLARE @new_order1 NVARCHAR(100)
DECLARE @new_order2 NVARCHAR(100)
DECLARE @Sql NVARCHAR(4000)
DECLARE @SqlCount NVARCHAR(4000)
DECLARE @Top int
if(@sys_Begin <=0)
set @sys_Begin=0
else
set @sys_Begin=@sys_Begin-1
IF ISNULL(@sys_Where,'') = ''
SET @new_where1 = ' '
ELSE
SET @new_where1 = ' WHERE ' + @sys_Where
IF ISNULL(@sys_Order,'') <> ''
BEGIN
SET @new_order1 = ' ORDER BY ' + Replace(@sys_Order,'desc','')
SET @new_order1 = Replace(@new_order1,'asc','desc')
SET @new_order2 = ' ORDER BY ' + @sys_Order
END
ELSE
BEGIN
SET @new_order1 = ' ORDER BY ID DESC'
SET @new_order2 = ' ORDER BY ID ASC'
END
SET @SqlCount = 'SELECT @RCount=COUNT(1),@PCount=CEILING((COUNT(1)+0.0)/'
+ CAST(@sys_PageSize AS NVARCHAR)+') FROM ' + @sys_Table + @new_where1
EXEC SP_EXECUTESQL @SqlCount,N'@RCount INT OUTPUT,@PCount INT OUTPUT',
@RCount OUTPUT,@PCount OUTPUT
IF @sys_PageIndex > CEILING((@RCount+0.0)/@sys_PageSize) --如果输入的当前页数大于实际总页数,则把实际总页数赋值给当前页数
BEGIN
SET @sys_PageIndex = CEILING((@RCount+0.0)/@sys_PageSize)
END
set @sql = 'select '+ @sys_fields +' from ' + @sys_Table + ' w1 '
+ ' where '+ @sys_Key +' in ('
+'select top '+ ltrim(str(@sys_PageSize)) +' ' + @sys_Key + ' from '
+'('
+'select top ' + ltrim(STR(@sys_PageSize * @sys_PageIndex + @sys_Begin)) + ' ' + @sys_Key + ' FROM '
+ @sys_Table + @new_where1 + @new_order2
+') w ' + @new_order1
+') ' + @new_order2
print(@sql)
Exec(@sql)
GO