43 lines
1.3 KiB
MySQL
43 lines
1.3 KiB
MySQL
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-- Copyright 2018 Tanel Poder. All rights reserved. More info at http://tanelpoder.com
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-- Licensed under the Apache License, Version 2.0. See LICENSE.txt for terms & conditions.
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EXEC EXECUTE IMMEDIATE 'drop table t_children'; EXCEPTION WHEN OTHERS THEN NULL;
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CREATE TABLE t_children AS SELECT rownum a, 'zzz' b FROM dual CONNECT BY LEVEL<=1000;
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CREATE INDEX i_children ON t_children(a);
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-- deliberately gathering a histogram
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EXEC DBMS_STATS.GATHER_TABLE_STATS(user,'T_CHILDREN',method_opt=>'FOR COLUMNS A SIZE 254');
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-- this is the crap setting
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ALTER SESSION SET cursor_sharing = similar;
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@saveset
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SET PAGES 0 HEAD OFF TRIMOUT OFF TRIMSPOOL OFF ARRAYSIZE 5000 TERMOUT OFF
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SPOOL tmp_lotschildren.sql
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SELECT 'SELECT COUNT(*) FROM t_children WHERE a = '||TO_CHAR(ABS(DBMS_RANDOM.RANDOM))||';'
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FROM dual CONNECT BY LEVEL <= 100000;
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SPOOL OFF
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@loadset
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PROMPT Now run @tmp_lotschildren.sql
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-- this hack is not working, must use plain SQL instead of plsql
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-- ALTER SESSION SET session_cached_cursors = 0;
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-- ALTER SESSION SET "_close_cached_open_cursors" = TRUE;
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-- ALTER SESSION SET plsql_optimize_level = 0;
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--
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-- DECLARE
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-- j NUMBER;
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-- x NUMBER;
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-- BEGIN
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-- EXECUTE IMMEDIATE 'SELECT COUNT(*) FROM t_children WHERE a = '||TO_CHAR(ABS(DBMS_RANDOM.RANDOM)) INTO j;
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-- x:=x+j;
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-- COMMIT;
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-- END;
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-- /
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