oracle比较快的分页sql
方案1 适用于oracle9i以上!
select * from
(select row_number() over(order by sendid desc) rn,m.* from xxt_msgreceive m )
where rn <1010 and rn>=1000
方案2
SELECT * from (SELECT A.*, ROWNUM RN from (SELECT * from xxt_msg where sendstatus=1 order by msgid desc) A WHERE ROWNUM <= 4010)WHERE RN >=4000;
经测试,方案2速度要快
相关文档:
session状态:
STATUS VARCHAR2(8) Status of the session:
ACTIVE - Session currently executing SQL
INACTIVE - sql及其session没有释放或正常退出......
KILLED - Session marked to be killed
CACHED - Session temporarily cached for use by Oracle*XA
SNIPED - Session inactive, waiting on the clie ......
文章来源:Http://www.simple-talk.com
原文地址:http://www.simple-talk.com/sql/learn-sql-server/managing-transaction-logs-in-sql-server/
原作者:Robert Sheldon
翻译:三晋一枝花
译文原地址:http://prj.souty.cn/Admin/Knowledges/ShowKnowledge.aspx?id=44dbde74-d2c5-41a5-a8e9-375ba7103025
在 SQL Serv ......
转自:http://jianghaifeng.blogchina.com/3841741.html
SQL结构化查询字符串的改写,是实现数据库查询性能提升的最现实、最有效的手段,有时甚至是唯一的手段,比如在不允许大幅度修改现有数据库结构的情况下。
通过优化SQL语句提高查询性能的关键是:
根据实际需求情况,建立合适的索引;
......
CREATE FUNCTION dbo.UF_GetInvoiceSerials( @bizCode VARCHAR(10))
RETURNS VARCHAR(100)
AS
BEGIN
DECLARE @ret AS VARCHAR(1000)
SELECT @ret=Coalesce(@ret + ', ','') +
CASE e.ID
  ......