full text index 探秘（1）
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本文链接地址: full text index 探秘（1）
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[oracle@roger ~]$ sqlplus "/as sysdba" SQL*Plus: Release 10.2.0.4.0 - Production on Sun Aug 28 17:17:45 2011 Copyright (c) 1982, 2007, Oracle. All Rights Reserved. Connected to an idle instance. |
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SQL> startup ORACLE instance started. Total System Global Area 167772160 bytes Fixed Size 1266392 bytes Variable Size 71306536 bytes Database Buffers 92274688 bytes Redo Buffers 2924544 bytes Database mounted. Database opened. SQL> create user text_idx identified by text_idx; User created. SQL> grant resource ,connect,ctxapp to text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_CLS TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_DDL TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_DOC TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_OUTPUT TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_QUERY TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_REPORT TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_THES TO text_idx; Grant succeeded. SQL> GRANT EXECUTE ON CTXSYS.CTX_ULEXER TO text_idx; Grant succeeded. SQL> conn text_idx/text_idx Connected. SQL> CREATE TABLE docs (id NUMBER PRIMARY KEY, text VARCHAR2(500)); Table created. SQL> INSERT INTO docs VALUES(1, 'http://www.itpub.net/thread-1475450-1-1.html'); 1 row created. SQL> INSERT INTO docs VALUES(2, 'http://www.yesky.com/285/1942785_1.shtml'); 1 row created. SQL> INSERT INTO docs VALUES(3, 'http://www.baidu.com/s?tn=chenly082=4391'); 1 row created. SQL> INSERT INTO docs VALUES(4, 'file:///D:/oracle---官方文档/B19306_01/B19306_01/text.102/b14217/quicktour.htmi1008362'); 1 row created. SQL> INSERT INTO docs VALUES(5, 'file:///D:/oracle---官方文档/B19306_01/B19306_01/text.102/b14217/acase.htm#g637598'); 1 row created. SQL> INSERT INTO docs VALUES(6, 'http://database.51cto.com/art/201104/252898.htm'); 1 row created. SQL> commit; Commit complete. SQL> select count(*) from docs; COUNT(*) ---------- 6 SQL> col text for a50 SQL> set lines 120 SQL> SELECT id, text FROM docs WHERE CONTAINS(text, 'baidu', 1) > 0; ID TEXT ---------- -------------------------------------------------- 3 http://www.baidu.com/s?tn=chenly082=4391 SQL> set autot traceonly SQL> SELECT id, text FROM docs WHERE CONTAINS(text, 'baidu', 1) > 0; Execution Plan ---------------------------------------------------------- Plan hash value: 3588628665 ---------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ---------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 277 | 4 (0)| 00:00:01 | | 1 | TABLE ACCESS BY INDEX ROWID| DOCS | 1 | 277 | 4 (0)| 00:00:01 | |* 2 | DOMAIN INDEX | IDX_DOCS | | | 4 (0)| 00:00:01 | ---------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 2 - access("CTXSYS"."CONTAINS"("TEXT",'baidu',1)>0) Note ----- - dynamic sampling used for this statement Statistics ---------------------------------------------------------- 11 recursive calls 0 db block gets 18 consistent gets 0 physical reads 0 redo size 500 bytes sent via SQL*Net to client 400 bytes received via SQL*Net from client 2 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 1 rows processed SQL> create sequence seq_docs 2 minvalue 1 3 nomaxvalue 4 start with 7 5 increment by 1 6 nocycle 7 cache 10; Sequence created. SQL> begin 2 for i in 1..100 loop 3 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/'); 4 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=210'); 5 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=216'); 6 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=201'); 7 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=196'); 8 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=219'); 9 commit; 10 end loop; 11 end; 12 / PL/SQL procedure successfully completed. SQL> select count(*) from docs; COUNT(*) ---------- 606 SQL> begin 2 for i in 1..1000 loop 3 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/'); 4 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=210'); 5 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=216'); 6 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=201'); 7 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=196'); 8 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=219'); 9 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=205'); 10 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=206'); 11 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=207'); 12 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=199'); 13 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=208'); 14 commit; 15 end loop; 16 end; 17 / PL/SQL procedure successfully completed. SQL> select count(*) from docs; COUNT(*) ---------- 11606 SQL> set timing on SQL> begin 2 for i in 1..10000 loop 3 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/'); 4 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=210'); 5 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=216'); 6 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=201'); 7 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=196'); 8 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=219'); 9 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=205'); 10 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=206'); 11 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=207'); 12 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=199'); 13 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=208'); 14 commit; 15 end loop; 16 end; 17 / PL/SQL procedure successfully completed. Elapsed: 00:03:43.23 SQL> select count(*) from docs; COUNT(*) ---------- 121606 Elapsed: 00:00:00.05 SQL> select count(*) from docs where CONTAINS(text,'p=210') > 0; COUNT(*) ---------- 0 SQL> select count(*) from docs where CONTAINS(text,'killdb') >0; COUNT(*) ---------- 0 SQL> EXEC CTX_DDL.SYNC_INDEX('idx_docs', '5m'); PL/SQL procedure successfully completed. SQL> select count(*) from docs where CONTAINS(text,'p=210') > 0; COUNT(*) ---------- 110500 SQL> SELECT count(*) FROM docs WHERE CONTAINS(text,'killdb') > 0; COUNT(*) ---------- 121600 |
从这里看出 同步index的重要性了,下面来创建job 来进行定期的同步index以及优化。
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SQL> create or replace procedure sync_idx_docs as 2 begin 3 ctx_ddl.sync_index('idx_docs'); 4 end; 5 / Procedure created. SQL> VARIABLE job_no number; SQL> BEGIN 2 DBMS_JOB.SUBMIT(:job_no,'sync_idx_docs();', 3 SYSDATE, 'SYSDATE + 1'); 4 commit; 5 END; 6 / PL/SQL procedure successfully completed. SQL> create or replace procedure optimize_idx_docs as 2 begin 3 ctx_ddl.optimize_index('idx_docs','FULL'); 4 end; 5 / Procedure created. SQL> VARIABLE job_no number; SQL> BEGIN 2 DBMS_JOB.SUBMIT(:job_no,'optimize_idx_docs();', 3 SYSDATE, 'SYSDATE + 1'); 4 commit; 5 END; 6 / PL/SQL procedure successfully completed. SQL> col INTERVAL for a25 SQL> select JOB,LOG_USER,SCHEMA_USER,INTERVAL,LAST_DATE from user_jobs; JOB LOG_USER SCHEMA_USER INTERVAL LAST_DATE ---------- ------------- --------------- ---------------- --------- 21 TEXT_IDX TEXT_IDX SYSDATE + 1 28-AUG-11 22 TEXT_IDX TEXT_IDX SYSDATE + 1 28-AUG-11 ---启动如上2个job任务 SQL> execute dbms_job.run(21); PL/SQL procedure successfully completed. SQL> execute dbms_job.run(22); PL/SQL procedure successfully completed. SQL> alter table docs add owner varchar2(10); Table altered. SQL> update docs set owner='Roger'; 121606 rows updated. SQL> commit; Commit complete. |
下面来测试，如果表docs dml操作比较频繁，那么对于select语句来说，是否有较大的影响？
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SQL> select /*+ no_index(docs SYS_C005195)*/ 2 count(*) 3 from docs 4 where contains(text, 'p=199') > 0 5 and id > 10500 6 and id < 10800; Elapsed: 00:00:00.09 Execution Plan ---------------------------------------------------------- Plan hash value: 1092983528 ----------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ----------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 277 | 4 (0)| 00:00:01 | | 1 | SORT AGGREGATE | | 1 | 277 | | | |* 2 | TABLE ACCESS BY INDEX ROWID| DOCS | 1 | 277 | 4 (0)| 00:00:01 | |* 3 | DOMAIN INDEX | IDX_DOCS | | | 4 (0)| 00:00:01 | ----------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 2 - filter("ID">10500 AND "ID"<10800) 3 - access("CTXSYS"."CONTAINS"("TEXT",'p=199')>0) Note ----- - dynamic sampling used for this statement ---session 1 SQL> show user USER is "TEXT_IDX" SQL> begin 2 for i in 1 .. 15000 loop 3 if mod(i, 2) = 0 then 4 update docs 5 set owner = 'killdb' 6 where id = i 7 and id > 10000 8 and id < 15000; 9 commit; 10 end if; 11 end loop; 12 commit; 13 end; 14 / PL/SQL procedure successfully completed. ---session 2 SQL> select /*+ no_index(docs SYS_C005195)*/ 2 id,owner,text 3 from docs 4 where contains(text, 'p=199') > 0 5 and id > 10700 6 and id < 10800; 90 rows selected. Elapsed: 00:00:00.19 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 17447 consistent gets 0 physical reads 1024 redo size 4691 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.35 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 21322 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.76 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 19518 consistent gets 0 physical reads 1856 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.37 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15409 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.30 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 20226 consistent gets 0 physical reads 64 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.32 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 17881 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.42 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15728 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.49 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 17406 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.25 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 16768 consistent gets 0 physical reads 128 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.40 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 16515 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.34 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 16046 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.34 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 19300 consistent gets 0 physical reads 1856 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:02.92 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 19860 consistent gets 0 physical reads 1216 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.45 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15569 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.42 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15120 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.21 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 17201 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.14 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 18365 consistent gets 0 physical reads 384 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.59 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 17998 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.29 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 14515 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.11 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15595 consistent gets 0 physical reads 704 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.23 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15675 consistent gets 0 physical reads 768 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.20 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 15584 consistent gets 0 physical reads 0 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed SQL> / 90 rows selected. Elapsed: 00:00:00.14 Statistics ---------------------------------------------------------- 13 recursive calls 0 db block gets 18380 consistent gets 0 physical reads 1344 redo size 4689 bytes sent via SQL*Net to client 455 bytes received via SQL*Net from client 7 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 90 rows processed |
从上面的测试不难看出，对于DML操作频繁的话，对全文索引来说，还是有较大的影响的。
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SQL> begin 2 for i in 1 .. 15000 loop 3 if mod(i, 2) = 0 then 4 update docs 5 set owner = 'google' 6 where id = i 7 and id > 50000 8 and id < 10000; 9 commit; 10 end if; 11 end loop; 12 commit; 13 end; 14 / PL/SQL procedure successfully completed. Elapsed: 00:00:02.25 SQL> exec ctx_ddl.optimize_index('idx_docs','rebuild') ; PL/SQL procedure successfully completed. Elapsed: 00:00:02.84 SQL> begin 2 for i in 1 .. 15000 loop 3 if mod(i, 2) = 0 then 4 update docs 5 set owner = 'baidu' 6 where id = i 7 and id > 50000 8 and id < 10000; 9 commit; 10 end if; 11 end loop; 12 commit; 13 end; 14 / PL/SQL procedure successfully completed. Elapsed: 00:00:02.23 SQL> exec ctx_ddl.optimize_index('idx_docs','FULL') ; PL/SQL procedure successfully completed. Elapsed: 00:00:00.45 SQL> begin 2 for i in 1..10000 loop 3 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/'); 4 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=210'); 5 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=216'); 6 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=201'); 7 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=196'); 8 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=219'); 9 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=205'); 10 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=206'); 11 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=207'); 12 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=199'); 13 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=208'); 14 commit; 15 end loop; 16 end; 17 / begin * ERROR at line 1: ORA-29875: failed in the execution of the ODCIINDEXINSERT routine ORA-20000: Oracle Text error: DRG-50857: oracle error in textindexmethods.ODCIIndexInsert ORA-00604: error occurred at recursive SQL level 2 ORA-01013: user requested cancel of current operation ORA-06512: at "CTXSYS.DRUE", line 160 ORA-06512: at "CTXSYS.TEXTINDEXMETHODS", line 633 ORA-06512: at line 13 Elapsed: 00:01:09.73 SQL> select count(*) from docs; COUNT(*) ---------- 138898 Elapsed: 00:00:00.35 SQL> exec ctx_ddl.optimize_index('idx_docs','FULL') ; PL/SQL procedure successfully completed. Elapsed: 00:00:00.48 SQL> begin 2 for i in 1..10000 loop 3 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/'); 4 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=210'); 5 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=216'); 6 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=201'); 7 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=196'); 8 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=219'); 9 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=205'); 10 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=206'); 11 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=207'); 12 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=199'); 13 INSERT INTO docs(id, text) VALUES(seq_docs.NEXTVAL, 'http://www.killdb.com/?p=208'); 14 commit; 15 end loop; 16 end; 17 / begin * ERROR at line 1: ORA-29875: failed in the execution of the ODCIINDEXINSERT routine ORA-20000: Oracle Text error: DRG-50857: oracle error in textindexmethods.ODCIIndexInsert ORA-01013: user requested cancel of current operation ORA-06512: at "CTXSYS.DRUE", line 160 ORA-06512: at "CTXSYS.TEXTINDEXMETHODS", line 633 ORA-06512: at line 12 Elapsed: 00:01:06.17 SQL> exec ctx_ddl.optimize_index('idx_docs','rebuild') ; PL/SQL procedure successfully completed. Elapsed: 00:00:02.09 SQL> select count(*) from docs; COUNT(*) ---------- 156091 Elapsed: 00:00:00.01 |
有人说优化index的时候，使用rebuild比full快很多，但是我测试恰恰相反，不知道为啥。
最后总结下：
1. DML操作较为频繁表，对全文索引一定影响，但是如果说必须使用该功能，那么也没办法,
2. 至于说为什么有一定影响，其实原理都一样的，因为逻辑读的消耗会增加，必然影响性能。
该功能是从oracle 9i引入的，10g，11g都分别有一定的改变，下一篇文章将会进行描述。
3 Responses to “full text index 探秘（1）”
这篇文章 是不是漏了建索引这一步:)
CREATE INDEX IDX_DOCS ON docs(text) INDEXTYPE IS CTXSYS.CONTEXT;
看的很仔细 确实是漏了。。。
Thank you for the post
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