the SELECT he mentioned is a native SQL command like

SELECT a_session FROM sessions WHERE id='7032f2c7f5a2c721a483dc75fc295
+95e';
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If you did that it may show you something like this.

$D = {'forename' => 'forename','timein' => 1489204868,'_SESSION_ID' =>
+ 'eb62615586d9b8a0f14f0dd3d820bf70','username' => 'username','_SESSIO
+N_ETIME' => 604800,'_SESSION_CTIME' => 1489204868,'_SESSION_REMOTE_AD
+DR' => '192.168.231.211','lastname' => 'lastname','user_id' => 'uid',
+'isloggedin' => 1,'_SESSION_ATIME' => 1489204868,'timeout' => 0,'atte
+mpts' => 0};;$D
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I am useing the native file support in CGI:Session, it stores each session record in its own file named cgisess_SID where SID is the contents of the _SESSION_ID key. as i suspected the data is a Dumper like structure of the _DATA keys value.