oracle 中的表分区

当数据库的数据不断扩大时，这时可以考虑是用表分区，查询时可以根据表分区查找，节省时间从而提高查询效率。

Connected to Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 
Connected as system
 
SQL> 
SQL> create tablespace CUS_TS01 datafile 'g://CUS_TS01' size 5m;
 
Tablespace created
SQL> create tablespace CUS_TS02 datafile 'g://CUS_TS02' size 5m;
 
Tablespace created
SQL> create tablespace CUS_TS03 datafile 'g://CUS_TS03' size 5m;
 
Tablespace created
 
SQL> 
SQL> CREATE TABLE MYCUSTOMER
  2  (
  3      CUSTOMER_ID NUMBER NOT NULL PRIMARY KEY,
  4      FIRST_NAME  VARCHAR2(30) NOT NULL,
  5      SEX       CHAR(1)
  6  )
  7  PARTITION BY RANGE (CUSTOMER_ID)
  8  (
  9      PARTITION CUS_PART1 VALUES LESS THAN (10) TABLESPACE CUS_TS01,
 10      PARTITION CUS_PART2 VALUES LESS THAN (20) TABLESPACE CUS_TS02,
 11      PARTITION CUS_PART3 VALUES LESS THAN (maxvalue) TABLESPACE CUS_TS03
 12  );
 
Table created
 
SQL> 
SQL> declare
  2  begin
  3   for i in 1..100 loop
  4    insert into MYCUSTOMER values(i,'xm','m');
  5   end loop;
  6  end;
  7  /
 
PL/SQL procedure successfully completed

SQL> select count(*) cn from MYCUSTOMER;
 
        CN
----------
       100
SQL> select count(*) cn from MYCUSTOMER PARTITION (CUS_PART1);
 
        CN
----------
         9
SQL> select count(*) cn from MYCUSTOMER PARTITION (CUS_PART2);
 
        CN
----------
        10
SQL> select count(*) cn from MYCUSTOMER PARTITION (CUS_PART3);
 
        CN
----------
        81

本文仅供参考，标准按照 ORACLE 官方规定

http://docs.oracle.com/cd/E11882_01/server.112/e26088/statements_7002.htm#

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