oracle11g 怎么没有Index Skip Scan 是不是默认没了，有参数？？？
oracle11g 跳跃索引扫描
------解决方案--------------------
SQL> select * from v$version;
BANNER
--------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production
PL/SQL Release 11.1.0.6.0 - Production
CORE 11.1.0.6.0 Production
TNS for Linux: Version 11.1.0.6.0 - Production
NLSRTL Version 11.1.0.6.0 - Production
SQL> desc t
Name Null? Type
----------------------------------------- -------- ----------------------------
ID NUMBER
NAME VARCHAR2(10)
SEX CHAR(2)
SQL> create index idx_t on t (sex,id);
Index created.
SQL> analyze index idx_t compute statistics;
Index analyzed.
SQL> set autot trace exp
SQL> select /*+ index_ss(t) */ id from t where id=8;