ChiloUK has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I'm using DBI to connect to my database, like this "$oDbc = DBI->connect("dbi:Informix:$sDatabase",...). What I am having difficulties with is finding out what is stored in $oDbc. When I use the debug I get DBI::db=HASH(...) which I expect. But I can't figure out how to see what is stored in the hash. The reason I require it is I am thinking of putting this call in a loop, instead of bombing out if it doesn't connect, I sleep a while and give it another go. I therefore need to see the two instances of connected and not. from this I can make a decision on whether it is connected or will need retried. I will also put a counter within the loop so it only fails so many times. I've been searching and can't find how to do it. Please can someone enlighten me. Many thanks.

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Re: A Database Connection Question
by Corion (Patriarch) on Oct 08, 2015 at 15:59 UTC

    Have you looked at what the DBI documentation has to say about the word "connected"?

    Also, if the connection to the database fails, I would simply use the RaiseError attribute to find out:

    my $retries = 5;
my $dbh;
while( !$dbh and $retries --> 0 ) {
    my $connected = eval {
        $dbh DBI->connect( $dsn, $user, $pass, { RaiseError => 1, Prin
+tError => 0 );
        1
    };
    if( !$connected ) {
        warn "Couldn't connect to $dsn: $@; $retries retries left.";
    } else {
        last;
    };
};
if( $retries == 0 ) {
    die "Couldn't connect to $dsn after five (re)tries";
};

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      Many Thanks. I figured it out like this... while ( $switch == 0 ) { $switch = 1; $oDbc = DBI->connect("dbi:Informix:$sDatabase",'','' ) or $switch = 0; if (!$switch) { sleep 60; $counter++; } if ($counter == 120) { exit(0); } }
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Re: A Database Connection Question
by hippo (Archbishop) on Oct 08, 2015 at 16:00 UTC

    From the fine documentation:

    If the connect fails (see below), it returns undef and sets both $DBI::err and $DBI::errstr. (It does not explicitly set $!.) You should generally test the return status of connect and print $DBI::errstr if it has failed.

    So, you can check the return value for undef and/or the class vars mentioned.

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