Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation
 
PerlMonks  

Re: DBI confusion

by mje (Curate)
on Jul 23, 2008 at 08:30 UTC ( #699548=note: print w/ replies, xml ) Need Help??


in reply to DBI confusion

selectrow_arrayref can obviously find no rows to return in which case it returns undef:

perl -e 'use DBI;$h = DBI->connect("dbi:Oracle:","xxx","yyy");my $r = +$h->selectrow_arrayref("select 1 from dual where 1=0");use Data::Dump +er;print Dumper($r);' $VAR1 = undef;

Unfortunately, selectrow_arrayref also returns undef if there is an error:

perl -e 'use DBI;$h = DBI->connect("dbi:Oracle:","xxx","xxx",{RaiseErr +or => 0,PrintError => 0});my $r = $h->selectrow_arrayref("select 1 fr +om dualxx");use Data::Dumper;print Dumper($r);' $VAR1 = undef;

the error being "ORA-00942: table or view does not exist". Note I had to turn off RaiseError and PrintError to a) avoid DBI calling die and b) avoid DBI printing the error. To tell the difference between the two you need to set RaiseError and catch the die:

perl -e 'use DBI;$h = DBI->connect("dbi:Oracle:","xxx","xxx",{RaiseErr +or => 1,PrintError => 0});my $r; eval{$r = $h->selectrow_arrayref("se +lect 1 from dualxx")};if ($@) { print "Error $@ and DBI err is $DBI:: +err";} else {use Data::Dumper;print Dumper($r);}'

which outputs:

Error DBD::Oracle::db selectrow_arrayref failed: ORA-00942: table or view does not exist (DBD ERROR: error possibly near <*>; indicator at char 14 in 'select 1 from <*>dualxx') for Statement "select 1 from dualxx" at -e line 1.


Comment on Re: DBI confusion
Select or Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://699548]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others meditating upon the Monastery: (8)
As of 2014-12-27 11:45 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    Is guessing a good strategy for surviving in the IT business?





    Results (177 votes), past polls