41 lines
1.2 KiB
SQL
41 lines
1.2 KiB
SQL
-- 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: lotslios.sql
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-- Purpose: Generate Lots of Logical IOs for testing purposes
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--
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-- Author: Tanel Poder
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-- Copyright: (c) http://www.tanelpoder.com
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--
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-- Usage: @lotslios <number>
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-- @lotslios 100
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-- @lotslios 1000000
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--
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-- Other: As the script self-joins SYS.OBJ$ to itself the maximum number
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-- of rows processed (and LIOs generated) depends on the number
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-- of rows in SYS.OBJ$
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--
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--------------------------------------------------------------------------------
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prompt generate lots of LIOs by repeatedly full scanning through a small table...
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select
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/*+ monitor
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leading(a b c)
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use_nl(b) use_nl(c) use_nl(d)
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full(a) full(b) full(c) full(d) */
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count(*)
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from
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sys.obj$ a,
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sys.obj$ b,
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sys.obj$ c,
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sys.obj$ d
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where
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a.owner# = b.owner#
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and b.owner# = c.owner#
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and c.owner# = d.owner#
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and rownum <= &1
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/
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