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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">Hands up everyone who knew that running a qe90 in star was not a good idea.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Keep your hands up if you knew that an error indicating this would be printed into II_STAR_LOG … if you had that configured.<o:p></o:p></p>
<p class="MsoNormal">Something like:<o:p></o:p></p>
<p class="MsoNormal">!Thu Nov 29 11:30:31 2018 [25658,81A75F00] ace_trexy_ddb >>>>> set trace point qe90<o:p></o:p></p>
<p class="MsoNormal">!TPF 00000000019B0230: QE90 will crash the server before executing<o:p></o:p></p>
<p class="MsoNormal">!TPF 00000000019B0230: the loop to log and commit the next state<o:p></o:p></p>
<p class="MsoNormal">!TPF 00000000019B0230: of DX 5BFFC9FE 000E79EB.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Keep your hands up if you knew that no such message would be delivered to the front end where you might notice it.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Now for the top of the class…it’s quite a funny story when you get past the tragic elements and overriding sense of doom.<o:p></o:p></p>
<p class="MsoNormal">In your distributed database create a work table which we use to insert into the registered table…<o:p></o:p></p>
<p class="MsoNormal">create table work(<o:p></o:p></p>
<p class="MsoNormal"> a integer4 not null not default,<o:p></o:p></p>
<p class="MsoNormal"> b integer4 not null not default<o:p></o:p></p>
<p class="MsoNormal">) with nojournaling;<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">insert into work values (5,1);<o:p></o:p></p>
<p class="MsoNormal">insert into work values (5,2);<o:p></o:p></p>
<p class="MsoNormal">insert into work values (5,3);<o:p></o:p></p>
<p class="MsoNormal">insert into work values (5,4);<o:p></o:p></p>
<p class="MsoNormal">insert into work values (5,5);<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">set qep;<o:p></o:p></p>
<p class="MsoNormal">set trace point qe90;<o:p></o:p></p>
<p class="MsoNormal">\p\g<o:p></o:p></p>
<p class="MsoNormal">insert into test (a, b, tinsert)<o:p></o:p></p>
<p class="MsoNormal">select a, b, date('19-Nov-2018 12:00:00')<o:p></o:p></p>
<p class="MsoNormal">from work;<o:p></o:p></p>
<p class="MsoNormal">\p\g<o:p></o:p></p>
<p class="MsoNormal">commit;<o:p></o:p></p>
<p class="MsoNormal">\p\g<o:p></o:p></p>
<p class="MsoNormal">\q<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Now the star server crashes…<o:p></o:p></p>
<p class="MsoNormal">and leaves an uncommitted transaction in the log. <o:p></o:p></p>
<p class="MsoNormal">That transaction is holding a table level lock, which meant I had to reformat the friggen log file, recover my 140G database from backup and replay lots of dumps and journals.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I was very unhappy.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">FYI. lartool can actually remove the transaction from the log. Pity I thought about that after the recovery was started.<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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