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111 lines
3.5 KiB
Text
111 lines
3.5 KiB
Text
create table t0 (a int);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t1(a int);
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insert into t1 select A.a + B.a* 10 + C.a * 100 from t0 A, t0 B, t0 C;
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create table t10 (a int, b int, c int);
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insert into t10
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select
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A.a + 1000*B.a,
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A.a + 1000*B.a,
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A.a + 1000*B.a
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from t1 A, t0 B
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order by A.a+1000*B.a;
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#################################################################
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## Try a basic example
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flush status;
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create table t21 as
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select
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sum(b) over (order by a rows between 2 preceding and 2 following) as SUM_B
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES NO PASSES
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set sort_buffer_size=1024;
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flush status;
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create table t22 as
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select
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sum(b) over (order by a rows between 2 preceding and 2 following) as SUM_B
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES WITH PASSES
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include/diff_tables.inc [t21, t22]
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drop table t21, t22;
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#################################################################
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# Try many cursors
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set sort_buffer_size=default;
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flush status;
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create table t21 as
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select
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sum(b) over (order by a rows between 2 preceding and 2 following) as SUM_B1,
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sum(b) over (order by a rows between 5 preceding and 5 following) as SUM_B2,
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sum(b) over (order by a rows between 20 preceding and 20 following) as SUM_B3
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES NO PASSES
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set sort_buffer_size=1024;
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flush status;
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create table t22 as
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select
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sum(b) over (order by a rows between 2 preceding and 2 following) as SUM_B1,
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sum(b) over (order by a rows between 5 preceding and 5 following) as SUM_B2,
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sum(b) over (order by a rows between 20 preceding and 20 following) as SUM_B3
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES WITH PASSES
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include/diff_tables.inc [t21, t22]
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drop table t21, t22;
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#################################################################
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# Try having cursors pointing at different IO_CACHE pages
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# in the IO_CACHE
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set sort_buffer_size=default;
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flush status;
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create table t21 as
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select
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a,
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sum(b) over (order by a range between 5000 preceding and 5000 following) as SUM_B1
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES NO PASSES
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set sort_buffer_size=1024;
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flush status;
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create table t22 as
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select
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a,
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sum(b) over (order by a range between 5000 preceding and 5000 following) as SUM_B1
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from
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t10;
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select variable_name,
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case when variable_value > 0 then 'WITH PASSES' else 'NO PASSES' end as result
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from information_schema.session_status
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where variable_name like 'Sort_merge_passes';
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variable_name result
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SORT_MERGE_PASSES WITH PASSES
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include/diff_tables.inc [t21, t22]
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drop table t21, t22;
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#################################################################
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drop table t10;
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drop table t0,t1;
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