MSSQL如何转为ORACLE

刚开始学习存储过程，写了个MSSQL的，不太熟悉ORACLE的该怎么写。希望各位大侠帮忙
SQL code:

set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go





ALTER PROCEDURE [dbo].[proc_getTotal]--<getTotal, gjjktemp, getTotal>
-- Add the parameters for the stored procedure here

--declare
@tableNamed nvarchar(20),
@start nvarchar(20),
@end nvarchar(20),
@centerid varchar(20),
@stationid varchar(20),
@itemid int,
@itemcode varchar(20),
@a int output
AS
BEGIN
--set @tableNamed = 'R_Hour_Data'
--set @start = '2009-1-1 0:00:00'
--set @end = '2010-12-31 0:00:00'
--set @centerid = 86
--set @stationid = 6
--set @itemid = 12516
--set @itemcode = '1CV'
declare @countOne int
declare @countTwo int
declare @s nvarchar(4000)
declare @startyear nvarchar(4) --开始年
declare @endyear nvarchar(4) --结束年
declare @tableName nvarchar(40) --表名
declare @colName nvarchar(40) --列名
set @startyear = substring(@start,1,5)
set @endyear = substring(@end,1,5)

SET NOCOUNT ON;
if @tableNamed is not null
begin
set @s='select @i=count(*) from '+@tableNamed+'_'+@startyear+' as a where a.StaticDate >= '''+@start+''' and a.StaticDate<= '''+@end+''' and a.centerid = '+@centerid+' and a.stationid = '+@statio