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<TITLE>Transactions - How the DBI helps</TITLE>
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<H1>Transactions - How the DBI helps</H1>
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<LI><H2>Tools of the trade:
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<LI>Set AutoCommit off
<LI>Set RaiseError on
<LI>Wrap eval {
} around the code
<LI>Use $dbh->commit; and $dbh->rollback;
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<LI><H2>Disable AutoCommit via $dbh->{AutoCommit}=0 or $dbh->begin_work;
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<LI>to enable use of transactions
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<LI><H2>Enable RaiseError via $dbh->{RaiseError} = 1;
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<LI>to automatically 'throw an exception' when an error is detected
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<LI><H2>Add surrounding eval {
}
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<LI>catches the exception, the error text is stored in $@
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<LI><H2>Test $@ and then $dbh->rollback() if set
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<LI>note that a failed statement doesnt automatically trigger a transaction rollback</UL></UL></P>
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