I used:

use DBIx::Log4perl qw(:masks);

$DBIx::Log4perl::LogMask = DBIX_L4P_LOG_OUTPUT | DBIX_L4P_LOG_INPUT;

Log::Log4perl->init("myconfig.cfg");

$dbh = DBIx::Log4perl->connect($DSN, "user", "pass");
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Config-file:

log4perl.logger = FATAL, LOGFILE

log4perl.appender.LOGFILE=Log::Log4perl::Appender::File
log4perl.appender.LOGFILE.filename=logs/FATAL.TXT
log4perl.appender.LOGFILE.mode=append
log4perl.appender.LOGFILE.Threshold = ERROR

log4perl.appender.LOGFILE.layout=PatternLayout
log4perl.appender.LOGFILE.layout.ConversionPattern=[%r] %F %L %c - %m%
+n

log4perl.logger.DBIx.Log4perl=DEBUG, A1
log4perl.appender.A1=Log::Log4perl::Appender::File
log4perl.appender.A1.filename=logs/OK.txt
log4perl.appender.A1.mode=append
log4perl.appender.A1.layout=Log::Log4perl::Layout::SimpleLayout
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