- 浏览: 5616 次
最新评论
【转载】 yangtingkun: Oracle分页查询语句(四) 2011-01-12 16:42:50
分类: Oracle
最后的例子说明内部循环包含排序的情况:
SQL> CREATE TABLE T AS SELECT * FROM DBA_OBJECTS;
表已创建。
SQL> CREATE INDEX IND_T_OBJECT_NAME ON T (OBJECT_NAME);
索引已创建。
SQL> ALTER TABLE T MODIFY OBJECT_NAME NOT NULL;
表已更改。
SQL> EXEC DBMS_STATS.GATHER_TABLE_STATS(USER, 'T')
PL/SQL 过程已成功完成。
下面进行测试包含排序操作的分页查询。可以简单的将查询分为两种不同情况,第一种排序列就是索引列,这种可以利用索引读取,第二种排序列没有索引。
第一种情况又可以细分为:完全索引扫描和通过索引扫描定位到表记录两种情况。
无论是那种情况,都可以通过索引的全扫描来避免排序的产生。看下面的例子:
SQL> SET AUTOT TRACE
SQL> SELECT OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=26 Card=20 Bytes=1580)
1 0 VIEW (Cost=26 Card=20 Bytes=1580)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=26 Card=6361 Bytes=419826)
4 3 INDEX (FULL SCAN) OF 'IND_T_OBJECT_NAME' (NON-UNIQUE) (Cost=26 Card=6361 Bytes=108137)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
3 consistent gets
0 physical reads
0 redo size
576 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
10 rows processed
这种情况下,通过索引可以完全得到查询的结果,因此可以避免表扫描的产生,而且,由于索引已经是排序过的,因此通过索引的全扫描,连排序操作都省略了。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=43 Card=20 Bytes=1840)
1 0 VIEW (Cost=43 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=43 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=43 Card=6361 Bytes=133581)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=133581)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
673 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
由于不能仅仅通过索引扫描得到查询结果,这里Oracle选择了表扫描。这是由于初始化参数设置决定的。因此,建议在分页的时候使用FIRST_ROWS提示。
SQL> SELECT /*+ FIRST_ROWS */ OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=HINT: FIRST_ROWS (Cost=826 Card=20 Bytes=1840)
1 0 VIEW (Cost=826 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=826 Card=6361 Bytes=502519)
4 3 TABLE ACCESS (BY INDEX ROWID) OF 'T' (Cost=826 Card=6361 Bytes=133581)
5 4 INDEX (FULL SCAN) OF 'IND_T_OBJECT_NAME' (NON-UNIQUE) (Cost=26 Card=6361)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
22 consistent gets
0 physical reads
0 redo size
673 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
10 rows processed
使用了FIRST_ROWS提示后,Oracle不需要扫描全表,而且避免了排序操作。
下面讨论最后一种情况,排序列不是索引列。这个时候排序不可避免,但是利用给出分页格式,Oracle不会对所有数据进行排序,而是只排序前N条记录。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
8 )
9 )
10 WHERE RN BETWEEN 11 AND 20;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=6361 Bytes=585212)
1 0 VIEW (Cost=64 Card=6361 Bytes=585212)
2 1 COUNT
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
690 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=20 Bytes=1840)
1 0 VIEW (Cost=64 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
690 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
观察两种不同写法的ORDER BY步骤,一个是带STOPKEY的ORDER BY,另一个不带。在大数据量需要排序的情况下,带STOPKEY的效率要比不带STOPKEY排序的效率高得多。
SQL> INSERT INTO T SELECT T.* FROM T, USER_OBJECTS;
已创建407104行。
SQL> COMMIT;
提交完成。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME FROM
5 (
6 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
7 )
8 WHERE ROWNUM <= 20
9 )
10 WHERE RN >= 11;
已选择10行。
已用时间: 00: 00: 03.78
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=20 Bytes=1840)
1 0 VIEW (Cost=64 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
268 recursive calls
0 db block gets
6215 consistent gets
6013 physical reads
0 redo size
740 bytes sent via SQL*Net to client
385 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
6 sorts (memory)
0 sorts (disk)
10 rows processed
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME FROM
5 (
6 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
7 )
8 )
9 WHERE RN BETWEEN 11 AND 20;
已选择10行。
已用时间: 00: 00: 11.86
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=6361 Bytes=585212)
1 0 VIEW (Cost=64 Card=6361 Bytes=585212)
2 1 COUNT
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
26 recursive calls
12 db block gets
6175 consistent gets
9219 physical reads
0 redo size
737 bytes sent via SQL*Net to client
385 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
1 sorts (disk)
10 rows processed
观察两个查询语句的执行时间,以及统计信息中的排序信息。对于第一个查询语句,Oracle利用了ORDER BY STOPKEY方式进行排序,排序操作只排序需要的TOP N的数据,因此排序操作放到了内存中,而对于第二个查询语句来说,进行的数据的全排序,排序数据量大,排序操作不得不在磁盘上完成,因此耗时比较多。
通过上面的例子可以看出给出的标准分页查询格式,对于包含排序的操作仍然可以在很大程度上提高分页查询性能。
[@more@]
分类: Oracle
最后的例子说明内部循环包含排序的情况:
SQL> CREATE TABLE T AS SELECT * FROM DBA_OBJECTS;
表已创建。
SQL> CREATE INDEX IND_T_OBJECT_NAME ON T (OBJECT_NAME);
索引已创建。
SQL> ALTER TABLE T MODIFY OBJECT_NAME NOT NULL;
表已更改。
SQL> EXEC DBMS_STATS.GATHER_TABLE_STATS(USER, 'T')
PL/SQL 过程已成功完成。
下面进行测试包含排序操作的分页查询。可以简单的将查询分为两种不同情况,第一种排序列就是索引列,这种可以利用索引读取,第二种排序列没有索引。
第一种情况又可以细分为:完全索引扫描和通过索引扫描定位到表记录两种情况。
无论是那种情况,都可以通过索引的全扫描来避免排序的产生。看下面的例子:
SQL> SET AUTOT TRACE
SQL> SELECT OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=26 Card=20 Bytes=1580)
1 0 VIEW (Cost=26 Card=20 Bytes=1580)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=26 Card=6361 Bytes=419826)
4 3 INDEX (FULL SCAN) OF 'IND_T_OBJECT_NAME' (NON-UNIQUE) (Cost=26 Card=6361 Bytes=108137)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
3 consistent gets
0 physical reads
0 redo size
576 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
10 rows processed
这种情况下,通过索引可以完全得到查询的结果,因此可以避免表扫描的产生,而且,由于索引已经是排序过的,因此通过索引的全扫描,连排序操作都省略了。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=43 Card=20 Bytes=1840)
1 0 VIEW (Cost=43 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=43 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=43 Card=6361 Bytes=133581)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=133581)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
673 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
由于不能仅仅通过索引扫描得到查询结果,这里Oracle选择了表扫描。这是由于初始化参数设置决定的。因此,建议在分页的时候使用FIRST_ROWS提示。
SQL> SELECT /*+ FIRST_ROWS */ OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY OBJECT_NAME
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=HINT: FIRST_ROWS (Cost=826 Card=20 Bytes=1840)
1 0 VIEW (Cost=826 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=826 Card=6361 Bytes=502519)
4 3 TABLE ACCESS (BY INDEX ROWID) OF 'T' (Cost=826 Card=6361 Bytes=133581)
5 4 INDEX (FULL SCAN) OF 'IND_T_OBJECT_NAME' (NON-UNIQUE) (Cost=26 Card=6361)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
22 consistent gets
0 physical reads
0 redo size
673 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
10 rows processed
使用了FIRST_ROWS提示后,Oracle不需要扫描全表,而且避免了排序操作。
下面讨论最后一种情况,排序列不是索引列。这个时候排序不可避免,但是利用给出分页格式,Oracle不会对所有数据进行排序,而是只排序前N条记录。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
8 )
9 )
10 WHERE RN BETWEEN 11 AND 20;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=6361 Bytes=585212)
1 0 VIEW (Cost=64 Card=6361 Bytes=585212)
2 1 COUNT
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
690 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME
5 FROM
6 (
7 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
8 )
9 WHERE ROWNUM <= 20
10 )
11 WHERE RN >= 11;
已选择10行。
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=20 Bytes=1840)
1 0 VIEW (Cost=64 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
0 recursive calls
0 db block gets
81 consistent gets
0 physical reads
0 redo size
690 bytes sent via SQL*Net to client
503 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
10 rows processed
观察两种不同写法的ORDER BY步骤,一个是带STOPKEY的ORDER BY,另一个不带。在大数据量需要排序的情况下,带STOPKEY的效率要比不带STOPKEY排序的效率高得多。
SQL> INSERT INTO T SELECT T.* FROM T, USER_OBJECTS;
已创建407104行。
SQL> COMMIT;
提交完成。
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME FROM
5 (
6 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
7 )
8 WHERE ROWNUM <= 20
9 )
10 WHERE RN >= 11;
已选择10行。
已用时间: 00: 00: 03.78
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=20 Bytes=1840)
1 0 VIEW (Cost=64 Card=20 Bytes=1840)
2 1 COUNT (STOPKEY)
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY STOPKEY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
268 recursive calls
0 db block gets
6215 consistent gets
6013 physical reads
0 redo size
740 bytes sent via SQL*Net to client
385 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
6 sorts (memory)
0 sorts (disk)
10 rows processed
SQL> SELECT OBJECT_ID, OBJECT_NAME
2 FROM
3 (
4 SELECT ROWNUM RN, OBJECT_ID, OBJECT_NAME FROM
5 (
6 SELECT OBJECT_ID, OBJECT_NAME FROM T ORDER BY TIMESTAMP
7 )
8 )
9 WHERE RN BETWEEN 11 AND 20;
已选择10行。
已用时间: 00: 00: 11.86
Execution Plan
----------------------------------------------------------
0 SELECT STATEMENT Optimizer=CHOOSE (Cost=64 Card=6361 Bytes=585212)
1 0 VIEW (Cost=64 Card=6361 Bytes=585212)
2 1 COUNT
3 2 VIEW (Cost=64 Card=6361 Bytes=502519)
4 3 SORT (ORDER BY) (Cost=64 Card=6361 Bytes=260801)
5 4 TABLE ACCESS (FULL) OF 'T' (Cost=9 Card=6361 Bytes=260801)
Statistics
----------------------------------------------------------
26 recursive calls
12 db block gets
6175 consistent gets
9219 physical reads
0 redo size
737 bytes sent via SQL*Net to client
385 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
1 sorts (disk)
10 rows processed
观察两个查询语句的执行时间,以及统计信息中的排序信息。对于第一个查询语句,Oracle利用了ORDER BY STOPKEY方式进行排序,排序操作只排序需要的TOP N的数据,因此排序操作放到了内存中,而对于第二个查询语句来说,进行的数据的全排序,排序数据量大,排序操作不得不在磁盘上完成,因此耗时比较多。
通过上面的例子可以看出给出的标准分页查询格式,对于包含排序的操作仍然可以在很大程度上提高分页查询性能。
[@more@]
发表评论
-
ORCALE 密码修改
2015-09-24 09:43 279运行 cmd sqlplus/nolog c ... -
oracle证书
2015-09-24 09:41 0https://localhost:1158/em/con ... -
orcale个人总结
2015-07-02 10:08 0orcale 密码找回方法----------------- ... -
orcale配置中遇到的问题
2015-07-02 09:54 01 oracle登录错误:ORA-28000: ... -
orcale安装
2015-07-02 09:17 0Oracle11g----Win7 32位安装图例 h ... -
Oracle分页查询格式(十一)
2015-07-24 12:11 313Oracle分页查询格式(十一) 2009-06-05 22: ... -
Oracle分页查询格式(八)
2015-07-31 10:19 311Oracle分页查询格式(八) 2006-10-28 00:0 ... -
Oracle分页查询语句(七)
2015-07-31 10:19 341【转载】 yangtingkun: Oracle分页查询语句( ... -
Oracle分页查询语句(六)
2015-07-31 10:18 411Oracle分页查询语句(六) 2006-06-03 00:0 ... -
Oracle分页查询语句(五)
2015-07-31 10:18 254【转载】 yangtingkun: Oracle分页查询语句( ... -
Oracle分页查询语句(三)
2015-07-24 12:12 264Oracle分页查询语句(三) 2006-05-27 00:0 ... -
Oracle分页查询语句(二)
2015-07-24 12:12 311Oracle分页查询语句(二) 2006-05-23 00:0 ... -
Oracle分页查询语句(一)
2015-07-24 12:12 329【转载】 yangtingkun: Oracl ...
相关推荐
msql和oracle分页查询语句笔记
Oracle的分页查询语句以及Oracle分页的存储过程
Oracle分页查询语句的学习和示例演练
oracle分页查询语句sql
Oracle的分页查询语句
一些常用到的在oracle中的sql语句,也是我在网上找到的,分享给大家
网上搜集的oracle分页查询语句和性能分析
select * from (select a.*,rownum rn from (select * from tablename) a where rownum) where rn>2
用ORACLE的SQL语句实现多栏分页输出.RTF
oracle认证详解Oracle的几种分页查询语句! 值得下载看看!资源免费,大家分享!!
Oracle的分页查询语句基本上可以按照本文给出的格式来进行套用
NULL 博文链接:https://yan578351314.iteye.com/blog/911307
Oracle中实现分页查询的SQL命令 //curPage是当前页面,pageCount是每页显示行数 //rownum是伪列,相当于表中每一列的标识列(可以理解为行号),需要显式的提取出来并取一个别名
高效多条件 Oracle 分页存储过程 ,快速分页
几条常见的数据库分页SQL 语句,针对oracle,sqlserver,mysql三种常见数据库的分页显示。
环境: Oracle 9i 本例子使用简单的SQL语句实现Oracle数据库的分页动作。它没有使用PL/SQL语句(比如什么程序包、游标等),只是使用通用的、简单的SQL实现了...分页公式注释非常详细,是非常实用的Oracle分页语句!!
对于数据库中表的数据的 Web 显示,如果没有展示顺序的需要,而且因为满足条件的记录如此之多,就不得不对数据进行分页处理。常常用户并不是对所有数据都感兴趣的,或者大部分情况下,他们...看似相似的分页语句,在响
写好oracle的连接字符串和查询语句,调用程序中的方法可以很方便的实现分页功能。该方法中,将参数连接字符串,查询的sql语句,指定每页显示多少行,调用成功后,会返回页数,行数,还有查询的结果数据集。 使用...
mysql和oracle的分页语句
3大数据库(Sql-Server,MySql和Oracle)的分页SQL语句实现