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http://www.anysql.net/oracle/query_rewrite_01.html
Query Rewrite ÔÚÊý¾Ý²Ö¿âÊÇÊÇÒ»¸ö·Ç³£ÓÐÓõļ¼Êõ, TomÔÚ<<Effective Oracle by Design>>Ò»ÊéÖн«ÊµÌ廯ÊÓͼ(MView)³ÆÎªÊÇÊý¾Ý²Ö¿âµÄË÷Òý, ÕâÊÇÔÙÌùÇв»¹ýµÄÁË, ÔÚOLTPÖе±SELECTÓï¾äµÄËùÓеÄ×ֶζ¼ÔÚË÷ÒýÖÐʱ, Oracle¿ÉÒÔ²»´Ó±í¶ÁÊý¾Ý, ¶øÖ±½Ó´ÓË÷ÒýÖлñµÃÈ«²¿ÐÅÏ¢, ¶øQuery RewriteÔòÊÇͨ¹ý´´½¨Öмä±í, ÈÃOracle×Ô¶¯´Ó´´½¨µÄÖмä±í¶ÁÈ¡Êý¾Ý, ¶ø²»ÐèÒª´ÓÔ±í¶ÁÈ¡ÁË, Õâ¸öÖмä±í¿ÉÒÔÊÇÔ¤ÏÈjoinºÃµÄ»òÔ¤ÏȼÆËãºÃµÄÖмä½á¹û. ËûµÄʹÓþͺÍÒ»°ãµÄË÷ÒýͬÀíÁË, ËäÈ»ÄãÖ¸¶¨µÄ»¹ÊÇÄǸö´ó±í, µ«oracle¿ÉÒÔΪÄã×Ô¶¯Ê¶±ð¿ÉÒÔ´ÓÄǸö"Êý¾Ý²Ö¿âË÷Òý"ÖжÁÈ¡Êý¾Ý. ÏÂÃæÎÒÃÇ¿ÉÒÔÀ´¿´Ò»ÏÂ×î¼òµ¥µÄÀý×Ó:
SQL> CREATE TABLE DETAIL_TABLE
2 AS SELECT OWNER,OBJECT_NAME from sys.dba_objects;
Table created.
SQL> DESC DETAIL_TABLE
Name Null? Type
---------------------------------- -------- --------------
OWNER VARCHAR2(30)
OBJECT_NAME VARCHAR2(128)
SQL> CREATE MATERIALIZED VIEW MID_TABLE ENABLE QUERY REWRITE
2 AS
3 SELECT OWNER,COUNT(*) TABCNT from DETAIL_TABLE GROUP BY OWNER;
Materialized view created.
SQL> DESC MID_TABLE
Name  
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