一、实验说明：
操作系统：rhel 5.4 x86
数据库：Oracle 11g R2
二、操作步骤：
2.1、首先创建一个表t_btree，并创建B-Tree索引，索引键是object_name:
1 SQL> create table t_btree as select * from dba_objects; 2 3 Table created. 4 5 SQL> create index ind_btree on t_btree(object_name); 6 7 Index created.
接着是执行下面的查询语句两次：
1 SQL> set linesize 150; 2 SQL> set autotrace on; 3 SQL> select count(*) from t_btree where t_btree.object_name like '%ObjectStreamClass%'; 4 5 COUNT(*) 6 ---------- 7 84 8 9 10 Execution Plan 11 ---------------------------------------------------------- 12 Plan hash value: 3266099700 13 14 ----------------------------------------------------------------------------------- 15 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 16 ----------------------------------------------------------------------------------- 17 | 0 | SELECT STATEMENT | | 1 | 66 | 103 (0)| 00:00:02 | 18 | 1 | SORT AGGREGATE | | 1 | 66 | | | 19 |* 2 | INDEX FAST FULL SCAN| IND_BTREE | 12 | 792 | 103 (0)| 00:00:02 | 20 ----------------------------------------------------------------------------------- 21 22 Predicate Information (identified by operation id): 23 --------------------------------------------------- 24 25 2 - filter("T_BTREE"."OBJECT_NAME" IS NOT NULL AND 26 "T_BTREE"."OBJECT_NAME" LIKE '%ObjectStreamClass%') 27 28 Note 29 ----- 30 - dynamic sampling used for this statement (level=2) 31 32 33 Statistics 34 ---------------------------------------------------------- 35 28 recursive calls 36 0 db block gets 37 454 consistent gets 38 726 physical reads 39 0 redo size 40 422 bytes sent via SQL*Net to client 41 419 bytes received via SQL*Net from client 42 2 SQL*Net roundtrips to/from client 43 0 sorts (memory) 44 0 sorts (disk) 45 1 rows processed 46 47 SQL> select count(*) from t_btree where t_btree.object_name like '%ObjectStreamClass%'; 48 49 COUNT(*) 50 ---------- 51 84 52 53 54 Execution Plan 55 ---------------------------------------------------------- 56 Plan hash value: 3266099700 57 58 ----------------------------------------------------------------------------------- 59 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 60 ----------------------------------------------------------------------------------- 61 | 0 | SELECT STATEMENT | | 1 | 66 | 103 (0)| 00:00:02 | 62 | 1 | SORT AGGREGATE | | 1 | 66 | | | 63 |* 2 | INDEX FAST FULL SCAN| IND_BTREE | 12 | 792 | 103 (0)| 00:00:02 | 64 ----------------------------------------------------------------------------------- 65 66 Predicate Information (identified by operation id): 67 --------------------------------------------------- 68 69 2 - filter("T_BTREE"."OBJECT_NAME" IS NOT NULL AND 70 "T_BTREE"."OBJECT_NAME" LIKE '%ObjectStreamClass%') 71 72 Note 73 ----- 74 - dynamic sampling used for this statement (level=2) 75 76 77 Statistics 78 ---------------------------------------------------------- 79 0 recursive calls 80 0 db block gets 81 369 consistent gets 82 0 physical reads 83 0 redo size 84 422 bytes sent via SQL*Net to client 85 419 bytes received via SQL*Net from client 86 2 SQL*Net roundtrips to/from client 87 0 sorts (memory) 88 0 sorts (disk) 89 1 rows processed
2.2、创建表t_bmap，并创建BitMap索引：
1 SQL> create table t_bmap as select * from dba_objects; 2 3 Table created. 4 SQL> create bitmap index ind_bmap on t_bmap(object_name); 5 6 Index created。
执行之前的同样的语句查询：
1 SQL> select count(*) from t_bmap where t_bmap.object_name like '%ObjectStreamClass%'; 2 3 COUNT(*) 4 ---------- 5 84 6 7 8 Execution Plan 9 ---------------------------------------------------------- 10 Plan hash value: 891302759 11 12 ------------------------------------------------------------------------------------------ 13 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 14 ------------------------------------------------------------------------------------------ 15 | 0 | SELECT STATEMENT | | 1 | 66 | 263 (0)| 00:00:04 | 16 | 1 | SORT AGGREGATE | | 1 | 66 | | | 17 | 2 | BITMAP CONVERSION COUNT | | 12 | 792 | 263 (0)| 00:00:04 | 18 |* 3 | BITMAP INDEX FAST FULL SCAN| IND_BMAP | | | | | 19 ------------------------------------------------------------------------------------------ 20 21 Predicate Information (identified by operation id): 22 --------------------------------------------------- 23 24 3 - filter("T_BMAP"."OBJECT_NAME" IS NOT NULL AND "T_BMAP"."OBJECT_NAME" LIKE 25 '%ObjectStreamClass%') 26 27 Note 28 ----- 29 - dynamic sampling used for this statement (level=2) 30 31 32 Statistics 33 ---------------------------------------------------------- 34 28 recursive calls 35 0 db block gets 36 360 consistent gets 37 591 physical reads 38 0 redo size 39 422 bytes sent via SQL*Net to client 40 419 bytes received via SQL*Net from client 41 2 SQL*Net roundtrips to/from client 42 0 sorts (memory) 43 0 sorts (disk) 44 1 rows processed 45 46 SQL> select count(*) from t_bmap where t_bmap.object_name like '%ObjectStreamClass%'; 47 48 COUNT(*) 49 ---------- 50 84 51 52 53 Execution Plan 54 ---------------------------------------------------------- 55 Plan hash value: 891302759 56 57 ------------------------------------------------------------------------------------------ 58 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 59 ------------------------------------------------------------------------------------------ 60 | 0 | SELECT STATEMENT | | 1 | 66 | 263 (0)| 00:00:04 | 61 | 1 | SORT AGGREGATE | | 1 | 66 | | | 62 | 2 | BITMAP CONVERSION COUNT | | 12 | 792 | 263 (0)| 00:00:04 | 63 |* 3 | BITMAP INDEX FAST FULL SCAN| IND_BMAP | | | | | 64 ------------------------------------------------------------------------------------------ 65 66 Predicate Information (identified by operation id): 67 --------------------------------------------------- 68 69 3 - filter("T_BMAP"."OBJECT_NAME" IS NOT NULL AND "T_BMAP"."OBJECT_NAME" LIKE 70 '%ObjectStreamClass%') 71 72 Note 73 ----- 74 - dynamic sampling used for this statement (level=2) 75 76 77 Statistics 78 ---------------------------------------------------------- 79 0 recursive calls 80 0 db block gets 81 285 consistent gets 82 0 physical reads 83 0 redo size 84 422 bytes sent via SQL*Net to client 85 419 bytes received via SQL*Net from client 86 2 SQL*Net roundtrips to/from client 87 0 sorts (memory) 88 0 sorts (disk) 89 1 rows processed
2.3、创建表t_all，并创建全文索引：
1 SQL> create table t_all as select * from dba_objects; 2 3 Table created. 4 5 SQL> create index ind_all on t_all(object_name) indextype is ctxsys.context; 6 7 Index created.
下面改变一下查询语句，但是需要输出的结果是跟之前的一样：
1 SQL> select count(*) from t_all where contains(t_all.object_name,'%ObjectStreamClass%')>0; 2 3 COUNT(*) 4 ---------- 5 84 6 7 8 Execution Plan 9 ---------------------------------------------------------- 10 Plan hash value: 3532980284 11 12 ---------------------------------------------------------------------------- 13 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 14 ---------------------------------------------------------------------------- 15 | 0 | SELECT STATEMENT | | 1 | 78 | 4 (0)| 00:00:01 | 16 | 1 | SORT AGGREGATE | | 1 | 78 | | | 17 |* 2 | DOMAIN INDEX | IND_ALL | 35 | 2730 | 4 (0)| 00:00:01 | 18 ---------------------------------------------------------------------------- 19 20 Predicate Information (identified by operation id): 21 --------------------------------------------------- 22 23 2 - access("CTXSYS"."CONTAINS"("T_ALL"."OBJECT_NAME",'%ObjectStreamCl 24 ass%')>0) 25 26 Note 27 ----- 28 - dynamic sampling used for this statement (level=2) 29 30 31 Statistics 32 ---------------------------------------------------------- 33 2221 recursive calls 34 0 db block gets 35 2228 consistent gets 36 267 physical reads 37 0 redo size 38 422 bytes sent via SQL*Net to client 39 419 bytes received via SQL*Net from client 40 2 SQL*Net roundtrips to/from client 41 254 sorts (memory) 42 0 sorts (disk) 43 1 rows processed 44 45 SQL> select count(*) from t_all where contains(t_all.object_name,'%ObjectStreamClass%')>0; 46 47 COUNT(*) 48 ---------- 49 84 50 51 52 Execution Plan 53 ---------------------------------------------------------- 54 Plan hash value: 3532980284 55 56 ---------------------------------------------------------------------------- 57 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | 58 ---------------------------------------------------------------------------- 59 | 0 | SELECT STATEMENT | | 1 | 78 | 4 (0)| 00:00:01 | 60 | 1 | SORT AGGREGATE | | 1 | 78 | | | 61 |* 2 | DOMAIN INDEX | IND_ALL | 35 | 2730 | 4 (0)| 00:00:01 | 62 ---------------------------------------------------------------------------- 63 64 Predicate Information (identified by operation id): 65 --------------------------------------------------- 66 67 2 - access("CTXSYS"."CONTAINS"("T_ALL"."OBJECT_NAME",'%ObjectStreamCl 68 ass%')>0) 69 70 Note 71 ----- 72 - dynamic sampling used for this statement (level=2) 73 74 75 Statistics 76 ---------------------------------------------------------- 77 48 recursive calls 78 0 db block gets 79 348 consistent gets 80 0 physical reads 81 0 redo size 82 422 bytes sent via SQL*Net to client 83 419 bytes received via SQL*Net from client 84 2 SQL*Net roundtrips to/from client 85 0 sorts (memory) 86 0 sorts (disk) 87 1 rows processed