Enabling tracing
Per handle
$h->{TraceLevel} = $level;
$h->trace($level);
$h->trace($level, $filename); # $filename used for all handles
- Trace level only affects that handle and any new child handles created from it
- Child handles get trace level of parent in effect at time of creation
- Can be set via DSN: "dbi:Driver(TraceLevel=2):…"
Global (internal to application)
- Sets effective global default minimum trace level
Global (external to application)
- Enabled using DBI_TRACE environment variable
DBI_TRACE=digits same as DBI->trace(digits);
DBI_TRACE=digits=filename same as DBI->trace(digits, filename);