作者根据自己使用过的内容,把 常见 数据库 专区 href="http://dev.yesky.com/devsjk" target=_blank> 数据库 Sql Server,Oracle和MySQL的 分页 语句 做了介绍…… 我们在编写MIS系统和Web应用程序等系统时,都涉及到与 数据库 的交互,如果 数据库 中数据量
作者根据自己使用过的内容,把常见数据库专区 href="http://dev.yesky.com/devsjk" target=_blank>数据库Sql Server,Oracle和MySQL的分页语句做了介绍……
我们在编写MIS系统和Web应用程序等系统时,都涉及到与数据库的交互,如果数据库中数据量很大的话,一次检索所有的记录,会占用系统很大的资源,因此我们常常采用,需要多少数据就只从数据库中取多少条记录,即采用分页语句。根据自己使用过的内容,把常见数据库Sql Server,Oracle和MySQL的分页语句,从数据库表中的第M条数据开始取N条记录的语句总结如下:
SQL Server
从数据库表中的第M条记录开始取N条记录,利用Top关键字:注意如果Select语句中既有top,又有order by,则是从排序好的结果集中选择:
SELECT * FROM ( SELECT Top N * FROM (SELECT Top (M + N - 1) * FROM 表名称 Order by 主键 desc) t1 ) t2 Order by 主键 asc |
例如从表Sys_option(主键为sys_id)中从10条记录还是检索20条记录,语句如下:
SELECT * FROM ( SELECT TOP 20 * FROM (SELECT TOP 29 * FROM Sys_option order by sys_id desc) t1) t2 Order by sys_id asc |
Oralce数据库
从数据库表中第M条记录开始检索N条记录
SELECT * FROM (SELECT ROWNUM r,t1.* From 表名称 t1 where rownum where t2.r >= M |
例如从表Sys_option(主键为sys_id)中从10条记录还是检索20条记录,语句如下:
SELECT * FROM (SELECT ROWNUM R,t1.* From Sys_option where rownum Where t2.R >= 10 |
MySQL数据库
My sql数据库最简单,是利用mysql的LIMIT函数,LIMIT [offset,] rows从数据库表中M条记录开始检索N条记录的语句为:
以下是引用片段: SELECT * FROM 表名称 LIMIT M,N |
例如从表Sys_option(主键为sys_id)中从10条记录还是检索20条记录,语句如下:
以下是引用片段: select * from sys_option limit 10,20 |

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