61 lines
1.4 KiB
Plaintext
61 lines
1.4 KiB
Plaintext
drop table T1 purge;
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create table T1 tablespace USERS as
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select
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rownum id,
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case when rownum<4e4 then mod(rownum,500) else 999 end col1
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from ( select 1 just_a_column
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from DUAL
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connect by level <= 5e5
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)
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/
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drop table T2 purge;
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create table T2 tablespace USERS as
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select
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rownum id,
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case when rownum<8e5 then mod(rownum,500) else 999 end col1
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from ( select 1 just_a_column
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from DUAL
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connect by level <= 1e6
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)
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/
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alter system flush shared_pool;
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drop table Q purge;
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create table Q as
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select /*+ GATHER_PLAN_STATISTICS */
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T1.ID id1
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, T2.ID id2
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, T1.COL1 val
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from
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T1,
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T2
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where
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T1.COL1=150
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and T1.COL1=T2.COL1
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/
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select * from table(dbms_xplan.display_cursor(null,null,'ALLSTATS LAST +PEEKED_BINDS +PARALLEL +PARTITION +COST +BYTES'));
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exec dbms_stats.gather_table_stats(user,'T1', method_opt=>'for all columns size 1');
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exec dbms_stats.gather_table_stats(user,'T2', method_opt=>'for all columns size 1');
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exec dbms_stats.delete_table_stats('SYS','T1');
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exec dbms_stats.delete_table_stats('SYS','T2');
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exec dbms_stats.gather_table_stats(user,'T1', method_opt=>'for all columns size SKEWONLY');
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exec dbms_stats.gather_table_stats(user,'T2', method_opt=>'for all columns size SKEWONLY');
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@stats_col SYS T1 % % % %
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@stats_col SYS T2 % % % %
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@hist_cross_freq SYS T1 COL1 SYS T2 COL2
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