<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:SimSun;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:SimSun;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:SimSun;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:"Segoe UI";
panose-1:2 11 5 2 4 2 4 2 2 3;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
text-align:justify;
text-justify:inter-ideograph;
font-size:10.5pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
/* Page Definitions */
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 90.0pt 72.0pt 90.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="ZH-CN" link="blue" vlink="purple" style="text-justify-trim:punctuation">
<div class="WordSection1">
<p class="MsoNormal"><span lang="EN-US">Hi experts,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I see that FDO SQL server spatial provider uses an ODBC driver and I found the following about transaction in ODBC on MSDN website.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">“</span><i><span lang="EN-US" style="font-size:9.5pt;font-family:"Segoe UI","sans-serif";color:black">When an application turns autocommit off, the next statement sent to the database starts a transaction. The transaction
then remains in effect until the application calls <strong><span style="font-family:"Segoe UI","sans-serif"">SQLEndTran</span></strong> with either the SQL_COMMIT or SQL_ROLLBACK options. The command sent to the database after
<strong><span style="font-family:"Segoe UI","sans-serif"">SQLEndTran</span></strong> starts the next transaction.</span></i><span lang="EN-US">”<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">That means the transaction is not started
<b>explicitly </b>and it<b> </b>turns out that in manual commit mode(which is switched to when connection opens), any command can start a transaction.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">So considering the following scenario for SQL server spatial provider:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">FdoPtr<FdoIInsert> insertCommand1 = (FdoIInsert *) connection->CreateCommand(FdoCommandType_Insert);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">insertCommand1->SetFeatureClassName(…)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">insertCommand1->Execute();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">FdoPtr<FdoITransaction> transaction = connection->BeginTransaction();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">FdoPtr<FdoIInsert> insertCommand2 = (FdoIInsert *) connection->CreateCommand(FdoCommandType_Insert);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">insertCommand2->SetFeatureClassName(…)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">insertCommand2->Execute();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">transaction->Rollback()<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Actually if we look into the code, the BeginTransaction method simply calls rdbi_tran_begin which does nothing(not start an explicit transaction like using statement “begin transaction”) but only creates an transaction
entry for the connection.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Therefore, the first insert command creates a transaction implicitly and not until the transaction->Rollback() is executed that the transaction ends.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The problem is the first and the second insert commands are all rolled back which is not intended.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Is there somewhere I am missing or understanding incorrectly?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Sorry for the stupid question.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Sam<o:p></o:p></span></p>
</div>
</body>
</html>