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<P>Slide 51 of 80</P>
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<!-- <UL>
<H2>Enabling tracing</H2>
</UL></P>
<P><UL>
<LI><H2>Per handle
</H2>
<UL>
$h->trace($level);
<BR><BR>$h->trace($level, $filename);
</UL><LI>Only effects that handle and any new child handles created from it
<LI>Child handles get trace level of parent in effect at time of creation
</UL><UL>
<LI><H2>Global (internal to application)
</H2>
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DBI->trace(...);
<BR></UL><LI>Sets effective global default minimum trace level
</UL><UL>
<LI><H2>Global (external to application)
</H2>
<UL>
<LI>Enabled using DBI_TRACE environment variable
<UL>
DBI_TRACE=digits DBI->trace(digits);
<BR><BR>DBI_TRACE=filename DBI->trace(2, filename);
<BR>DBI_TRACE=digits=filename DBI->trace(digits, filename);</UL></UL></UL></P>
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