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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>For some reason I thought ZSQL method calls were atomic, but
they appear otherwise.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Using an eGenix mxODBC Database Connection at /Database/PoPy_database_connection
to a SQL Server 2000 back end, I have created a Python script to write SQL
commands and feed them in one large string:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>UPDATE equip SET workstation=1 WHERE eq_id=39315; <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>UPDATE node SET node='M28057' WHERE node_id=13451; <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>UPDATE materiel SET mat_nm='mm-M28057-H-01', owner='mmaslak',
datetime='2006/04/24 15:09:07.611 GMT-5' WHERE mat_id=39315;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>This all gets sent as one string to a ZSQL method where the first
two commands execute, but the third fails because it doesn't like the datetime string,
which indeed fails when I try it alone in the PoPy connection. Why, oh
why doesn't the whole thing fail like I might expect?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>When I wrap the call in a 'begin transaction … commit',
it becomes atomic. Nothing happens if part of it fails. Great. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>But failure is not detectable by the Python script. I have used
try/except and if/else blocks to ascertain failure. It thinks a non-commit is
AOK, not an exception. Is this function of the eGenix ODBC? Of MS SQL
Server 2K? Zope/ZSQL/Python?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>How can I detect failure and maintain atomicity?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Michael Maslak, Jr.<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Associate Software Engineer<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Anteon Corporation<o:p></o:p></span></font></p>
<p class=MsoAutoSig><st1:Street w:st="on"><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>294 Thames Ave</span></font></st1:Street><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Bay <st1:place w:st="on"><st1:City w:st="on">St. Louis</st1:City>,
<st1:State w:st="on">MS</st1:State> <st1:PostalCode w:st="on">39520</st1:PostalCode></st1:place></span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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