I am new to Perl and need some help.
In Mysql I have a table with a todo-List filled up.
At the beginning of my script, I want to add these values to "my %todo"
But I can't figure out how to do this...
Any idea?
3 Answers
OK, let's play martian rover though I'd rather see the code.
Do you use warnings; use strict? If not, do it. If yes, are there any warnings or errors?
If you put a print "while\n"; into your while loop, how many while's will you get on screen? How many records are there in the table?
If you use DBI, turn on exceptions: $dbh->RaiseError(1); ($dbh is you database handle here) before any operations with DB.
Comments
I don't understand why you ask for "load array" and specify a hash %todo, but if you want to read a table into memory once, you should look at the $dbh->selectall_arrayref() method.
Added: See if this get you started:
my $dsn = '...';
my $user = '...';
my $password = '...';
my $dbh = DBI->connect( $dsn, $user, $password, { RaiseError => 1, AutoCommit => 0 } );
my $sql = 'SELECT ... FROM Todo';
my %todo = ();
if (0) {
my $sth = $dbh->prepare( $sql );
$sth->execute();
while (my $aref = $sth->fetchrow_arrayref()) {
$todo{ $aref->[ 0 ] } = $aref->[ 1 ];
}
$sth->finish();
} else {
my $aref = $dbh->selectall_arrayref($sql);
for (@$aref) {
$todo{ $_->[ 0 ] } = $_->[ 1 ];
}
}
for (keys( %todo )) {
print $_, "\n", $todo{ $_ }, "\n\n";
}
my $rc = $dbh->disconnect();
4 Comments
perlbeginner
Sorry if I explained bad.. I want to load the content of the todo-tabe to stay in the %todo. I tried to use a while statement, but after the closing } the %todo is undefined. Any idea what I'm doing wrong?
Ekkehard.Horner
@perlbeginner - perhaps describing the table and the structure of the hash and/or showing some code will help.
perlbeginner
the table just has an unique id (id) and a column todo. the hash should have the same structure
Dave Cross
"Any idea what I'm doing wrong?" Without seeing some code, it's really hard to tell.
use strict;
use warnings;
my $dbh = $dbh->connect;
$dbh->{RaiseError} = 1;
my $sth = $dbh->prepare(q/select id, to_do from to_do_table/);
$sth->execute;
my %todo;
while(my ($id, $to_do) = $sth->fetchrow) {
$todo{$index_column} = $to_do;
}
$dbh->disconnect;
