132 lines
1.5 KiB
MySQL
132 lines
1.5 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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--------------------------------------------------------------------------------
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--
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-- File name: demo4.sql
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--
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-- Purpose: Advanced Oracle Troubleshooting Seminar demo script
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-- Causes optimizer to loop in CBO code for very long time
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--
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-- Author: Tanel Poder ( http://www.tanelpoder.com )
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-- Copyright: (c) Tanel Poder
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--
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--------------------------------------------------------------------------------
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prompt Starting demo4...
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set termout off feedback off
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drop table t;
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create table t as select * from all_objects where 1=0;
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exec dbms_stats.gather_table_stats(user,'T');
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alter session set "_optimizer_search_limit"=100;
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select *
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from
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t t1
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,t t2
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,t t3
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,t t4
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,t t5
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,t t6
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,t t7
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,t t8
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,t t9
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,t t10
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,t t11
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,t t12
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,t t13
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,t t14
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,t t15
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,t t16
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,t t17
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,t t18
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,t t19
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,t t20
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,t t21
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,t t22
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,t t23
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,t t24
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,t t25
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,t t26
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,t t27
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,t t28
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,t t29
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,t t30
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,t t31
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,t t32
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,t t33
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,t t34
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,t t35
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,t t36
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,t t37
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,t t38
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,t t39
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,t t40
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,t t41
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,t t42
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,t t43
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,t t44
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,t t45
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,t t46
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,t t47
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,t t48
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,t t49
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,t t50
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,t t51
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,t t52
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,t t53
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,t t54
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,t t55
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,t t56
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,t t57
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,t t58
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,t t59
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,t t60
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,t t61
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,t t62
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,t t63
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,t t64
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,t t65
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,t t66
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,t t67
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,t t68
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,t t69
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,t t70
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,t t71
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,t t72
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,t t73
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,t t74
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,t t75
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,t t76
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,t t77
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,t t78
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,t t79
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,t t80
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,t t81
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,t t82
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,t t83
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,t t84
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,t t85
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,t t86
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,t t87
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,t t88
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,t t89
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,t t90
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,t t91
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,t t92
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,t t93
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,t t94
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,t t95
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,t t96
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,t t97
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,t t98
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,t t99
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/
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set termout on feedback on
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