数据库分页大全（oracle利用解析函数row_number高效分页）

快来打我* 2022-07-15 23:07 251阅读 0赞

数据库分页大全（oracle利用解析函数row\_number高效分页）

Mysql分页采用limt关键字

**select \* from t\_order limit 5,10; **\#返回第6-15行数据    第一个参数是指要开始的地方，第二个参数是指每页显示多少条数据；注意：第一页用0表示。  
**select \* from  t\_order limit  5;** \#返回前5行   
**select \* from  t\_order limit  0,5; **\#返回前5行

Mssql 2000分页采用top关键字(20005以上版本也支持关键字rownum)

**Select top 10 \* from t\_order where id not in (select id from t\_order where id>5 )**; //返回第6到15行数据

其中10表示取10记录 5表示从第5条记录开始取

Oracle分页

①采用rownum关键字(三层嵌套)

**SELECT** \* **FROM **( **SELECT** A.\*,**ROWNUM**  num **FROM**   ( **SELECT** \* **FROM** t\_order ) A  **WHERE  ROWNUM**<=15 )  **WHERE** num>=5;**-**\-返回第5-15行数据

②采用row\_number解析函数进行分页(效率更高)

**SELECT** xx.\* **FROM**( **SELECT** t.\*,row\_number() over(**ORDER BY** o\_id)**AS** num **FROM** t\_order t )xx **WHERE** num **BETWEEN** 5 **AND** 15; --返回第5-15行数据

解析函数能用格式

函数() over(pertion by 字段 order by 字段);

Pertion 按照某个字段分区

Order 按照勒个字段排序

# 分页查询 #

数据库表结构及记录如下：

**1.根据rowid来分：**

16:31:48 SQL> select \* from passvehicleinfo p where rowid in ( select rid from (select rownum rn,rid from (select p.rowid rid,p.passvehicleid from passvehicleinfo p order by p.passvehicleid desc) view1 where rownum<10000) view2 where rn >9980)order by p.passvehicleid asc;

**![3252523_13150560757X8T.png][]2.按分析函数来分**

17:02:42 SQL> select \* from (select p.\*,row\_number() over (order by p.passvehicleid desc ) rk from passvehicleinfo p) where rk>9980 and rk<10000;

**![3252523_1315056076Fket.png][]3.按rownum来分**

17:07:38 SQL> select \* from (select view1.\*,rownum rn from (select p.\* from passvehicleinfo p order by p.passvehicleid desc) view1 where rownum<10000) view2 where rn>9980;

![3252523_13150560762460.png][]下面最主要介绍第三种：按rownum来分

**1. rownum 分页**

SELECT \* FROM emp;

**2. 显示rownum\[oracle分配的\]**

SELECT e.\*, ROWNUM rn FROM (SELECT \* FROM emp) e;

rn相当于Oracle分配的行的ID号

**3.挑选出6—10条记录**

先查出1-10条记录

SELECT e.\*, ROWNUM rn FROM (SELECT \* FROM emp) e WHERE ROWNUM <= 10;

如果后面加上rownum>=6是不行的，

**4. 然后查出6-10条记录**

SELECT \* FROM (SELECT e.\*, ROWNUM rn FROM (SELECT \* FROM emp) e WHERE ROWNUM <= 10) WHERE rn >= 6;

**5. 几个查询变化**

a. 指定查询列，只需要修改最里层的子查询

只查询雇员的编号和工资

SELECT \* FROM (SELECT e.\*, ROWNUM rn FROM (SELECT ename, sal FROM emp)

e WHERE ROWNUM <= 10) WHERE rn >= 6;

b. 排序查询，只需要修改最里层的子查询

工资排序后查询6-10条数据

SELECT \* FROM (SELECT e.\*, ROWNUM rn FROM (SELECT ename, sal FROM emp ORDER

by sal) e WHERE ROWNUM <= 10) WHERE rn >= 6;

在显示记录条目时往往要用到分页，一种常用的办法是利用各种数据库自带的定位接口对原始查询语句进行改写，从而只取出特定范围的某些记录。不同的数据库，查询定位接口是不一样的，下面做一汇总：

<table style="font-size:14px; margin:0px; padding:0px; outline:0px; font-family:Simsun; vertical-align:baseline; border-spacing:0px; width:620px; color:rgb(92,90,56); line-height:25px; border:1px solid; background-color:rgb(248,247,238)"> 
 <tbody style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;数据库 </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;分页查询语句 </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;说明 </td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;MySql </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;&nbsp;&nbsp;"QUERY_SQL&nbsp;limit ?,?"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;&nbsp;使用limit关键字，第一个"?"是起始行号， &nbsp; 第二个"?"是返回条目数</td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;Oracle </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;SELECT * FROM&nbsp; &nbsp;( SELECT A.*, ROWNUM RN&nbsp;&nbsp; FROM&nbsp;&nbsp; &nbsp;(QUERY_SQL&nbsp;) A&nbsp;&nbsp; WHERE ROWNUM&nbsp; &nbsp;&lt;= ？) WHERE RN &gt;= ？ </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;结合rownum关键字，利用嵌套三层select&nbsp; &nbsp;语句实现。第一个"?"表示终止行号， &nbsp; 第二个"?"表示其实行号</td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;Sql Server </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;尚无通用语句</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;可使用top n来返回前n条记录或使用存储过程</td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;DB2 </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;假设查询语句：select t1.* from t1 order &nbsp;by t1.id； 分页语句可为： &nbsp;"select * from ( select rownumber() over&nbsp; &nbsp; (order by t1.id) as row_, t1.* from t1&nbsp; &nbsp; order by t1.id) as temp_ where row_&nbsp; &nbsp; between ?+1 and ?"</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp; 返回两个"?"之间的记录</td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;InterBase </td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;“QUERY_SQL&nbsp;row ? to ?”</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp; 返回两个"?"之间的记录</td> 
 </tr> 
 <tr style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-family:inherit; vertical-align:baseline; font-weight:inherit"> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;PostgreSQL</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp;“QUERY_SQL&nbsp;limit ?&nbsp;offset ?”</td> 
 <td style="margin:0px; padding:0px; outline:0px; font-style:inherit; font-size:14px; font-family:inherit; vertical-align:baseline"> &nbsp; 第一个"?"为起始行号，第二个"?"代表 &nbsp; 返回记录数</td> 
 </tr> 
 </tbody> 
</table>

SQL Server   
关于分页 SQL 的资料许多，有的使用存储过程，有的使用游标。本人不喜欢使用游标，我觉得它耗资、效率低；使用存储过程是个不错的选择，因为存储过程是颠末预编译的，执行效率高，也更灵活。先看看单条 SQL 语句的分页 SQL 吧。   
方法1：   
适用于 SQL Server 2000/2005   
SELECT TOP 页大小 \* FROM table1 WHERE id NOT IN ( SELECT TOP 页大小\*(页数-1) id FROM table1 ORDER BY id ) ORDER BY id   
方法2：   
适用于 SQL Server 2000/2005   
SELECT TOP 页大小 \* FROM table1 WHERE id > ( SELECT ISNULL(MAX(id),0) FROM ( SELECT TOP 页大小\*(页数-1) id FROM table1 ORDER BY id ) A ) ORDER BY id   
方法3：   
适用于 SQL Server 2005   
SELECT TOP 页大小 \* FROM ( SELECT ROW\_NUMBER() OVER (ORDER BY id) AS RowNumber,\* FROM table1 ) A WHERE RowNumber > 页大小\*(页数-1)   
说明，页大小：每页的行数；页数：第几页。使用时，请把“页大小”以及“页大小\*(页数-1)”替换成数码。   
  
MYSQL   
SELECT \* FROM TT LIMIT 1,20   
SELECT \* FROM TT LIMIT 21,30   
/\*  
如果你是几千上万数据，就直接使用mysql自带的函数 limit的普通用法就ok了，如果是100万以上的数据，可能就要讲方法了，下面我们来做个百万级数据的分页查询语句.

> mysql> select \* from news where id>=(select id from news limit 490000,1) limit 10;    //0.18 sec  //很 明显,这 种方式胜出 .  
> mysql> select \* from news limit 490000,10  //0.22 sec;

\*/

以下的文章主要介绍的是MySQL分页的实际操作方案，其实关于实现MySQL分页的最简单的方法就是利用利用mysql数据库的LIMIT函数,LIMIT \[offset,\] rows可以从MySQL数据库表中第M条记录开始检索N条记录的语句为：

1.  SELECT \* FROM 表名称 LIMIT M,N

例如从表Sys\_option（主键为sys\_id)中从第10条记录开始检索20条记录，语句如下：

1.  select \* from sys\_option limit 10,20   
2.  select \* from table \[查询条件\] order by id limit ?,?

Oracle  
Oracle的分页查询语句基本上可以按照这篇了，下一篇文章会通过例子来申述。下面简单讨论一下多表联合的情况。对最多见的等值表连接查询，CBO 一般可能会采用两种连接方式NESTED LOOP以及HASH JOIN（MERGE JOIN效率比HASH JOIN效率低，一般CBO不会考虑）。在这里，由于使用了分页，因此指定了一个归回的最大记载数，NESTED LOOP在归回记载数跨越最大值时可以顿时遏制并将结果归回给中心层，而HASH JOIN必需处理完所有成集（MERGE JOIN也是）。那么在大部分的情况下，对分页查询选择NESTED LOOP作为查询的连接方法具有较高的效率（分页查询的时候绝大部分的情况是查询前几页的数据，越靠后面的页数访问概率越小）。  
因此，如果不介意在体系中使用HINT的话，可以将分页的查询语句改写为：  
SELECT /\*+ FIRST\_ROWS \*/ \* FROM  
(  
SELECT A.\*, ROWNUM RN  
FROM (SELECT \* FROM TABLE\_NAME) A  
WHERE ROWNUM <= 40  
)  
WHERE RN >= 21

[3252523_13150560757X8T.png]: /images/20220716/162897789e0048ebb3276c4b42419451.png
[3252523_1315056076Fket.png]: /images/20220716/d5fa9a5e3a6245b296bf1d5d4a542216.png
[3252523_13150560762460.png]: /images/20220716/b9cd93629f1f49df811f4fbf1d1c7962.png