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--删除customers表上除主键索引外的所有索引
sh@TESTDB11>@drop_customers_indexes.sql
--创建位图索引
CREATE BITMAP INDEX bidx_cust_credit_limit ON customers(cust_credit_limit) NOLOGGING COMPUTE STATISTICS;
--query11.sql
--虽然cust_credit_limit不具有很好的可选择度,但对其位图索引的count操作十分有效.
SET ECHO ON
SET TIMING ON
SET AUTOTRACE TRACEONLY
SET PAGESIZE 1000
@flush.sql
select count(*) as credit_limit from customers where cust_credit_limit = 10000;
SET TIMING OFF
SET AUTOTRACE OFF
--执行query11.sql
sh@TESTDB11>@query11.sql

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