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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve recently had a btree table which had grown to 8025535 pages with zero overflow. But after a modify it shrank to a little over 5000 pages.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My suspicion is that this table had grown to this size because it is daily getting a few hundred thousand rows inserted and then deleted. The key of the table is increasing and so deleted rows on the pages are never reused.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there an easy way to determine the number of ‘empty’ pages? I’ve started experimenting with modify table to table_debug [with table_option = 1|2|3], but I’m not seeing a smoking gun.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Eg.<o:p></o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">modify ae_current_state to table_debug with table_option=1;<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">********************************************************************<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">FHDR for TABLE: ae_current_state @ Pageno: 11143, Highwater FMAP: 251, FMAP's: 251<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> Allocation: 4, Extend: 16, Number of Extends: 42147<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">Last disc pageno: 8025539, Last FHDR/FMAP(s) pageno: 8025539<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> Last used pageno 8025534, Pages never used: 5<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">FMAP[0] @ Pageno: 11144, Base Pageno: 0<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> First free bit: 32096, Highwater bit: 32095<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> Last Free bit: 32095, Free Pages: 0, FHDR Hint: NO<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 32127 00000810 00000000 00000000 00000000 32000<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">FMAP[1] @ Pageno: 32084, Base Pageno: 32096<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> First free bit: 32096, Highwater bit: 32095<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> Last Free bit: 32095, Free Pages: 0, FHDR Hint: NO<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 64223 00000810 00000000 00000000 00000000 64096<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none">Or…<span style="font-size:10.0pt;font-family:"Lucida Console"">modify ae_current_state to table_debug with table_option=2;<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">********************************************************************<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console"">PAGE type DUMP for TABLE: ae_current_state, Total pages: 8025540<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 0 rLDDDDDDDD DLDDDDDDDD DDLDDDDDDD DDDDLDDDDD DDDDDDLDDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 50 DDDDDDDDLD DDDDDDDDDL DDDDDDDDDD LDDDDDDDDD DDLDDDDDDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 100 DDLDDDDDDD DDDLDDDDDD DDDDDLDDDD DDDDDDDLDD DDDDDDDDLD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 150 DDDDDDDDDD LDDDDDDDDL DDDDDDDDDL DDDDDDDDDD LDDDDDDDDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 200 DLDDDDDDDD DDLDDDDDDD DDDLDDDDDD DDDDLDDDDD DDDDDDDLDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 250 DDDDDDDDLD DDDDDDDDLD DDDDDDDDLD DDDDDDDDLD DDDDDDDDLD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 300 DDDDDDDDLD DDDDDDDDLD DDDDDDDDLD DDDDDDDDDL DDDDDDDDDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 350 LDDDDDDDDD DLDDDDDDDD DLDDDDDDDD DDDLDDDDDD DDDDLDDDDD<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Lucida Console""> 400 DDDDDLDDDD DDDDDDDLDD DDDDDDDLDD DDDDDDDDLD DDDDDDDDDL<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any ideas?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Martin Bowes<o:p></o:p></p>
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