in reply to Re^2: $dbh could not be passed to function unless another variable is also passed
in thread $dbh could not be passed to function unless another variable is also passed

That also works fine. SSCCE:

$ cat close.pl
#!/usr/bin/env perl 
use strict;
use warnings;
use DBI;

my $dbh = DBI->connect ('dbi:SQLite:dbname=foo', '', '');

close_db ($dbh);

sub close_db {
    my $dbh = $_[0];
    $dbh->disconnect or die "Could not disconnect: $DBI::errstr\n";
}
$ perl close.pl
$

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Re^4: $dbh could not be passed to function unless another variable is also passed
by tukusejssirs (Beadle) on Aug 08, 2019 at 14:01 UTC

    Probably I still miss something.

    I have another function called create_table and the db handle does not pass correctly (should I bless it?). I does work when I create the handle within the function.

    create_table($dbh, $table, "record_date char(20)");

sub create_table {
    use DBI;

    # Variables
    my $sth;
        # Database handle
        my $dbh = "$_[0]";

        # Table name and optionally schema name (schema.table)
        my $table = "$_[1]";

        # Columns and their type
        my $cols_type = "$_[2]";
    # } else {
    #     die RED, "ERROR: You have to supply database handle, table n
+ame, the columns list with their type and if you to disconnect the da
+tabase connection.\n       Stopped$!";
    # }

    # Create table
    $sth = $dbh->prepare("create table $table ($cols_type);");
    $sth->execute();
    print "INFO: The table has been created successfully.\n";

    return;
}

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      my $dbh = "$_[0]";

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      What is in $dbh and why do you force it to a string?

      Also, what is the error message? It is most likely something like Can't call method prepare on DBD::foo::dbh, but telling us the exact error message helps us much better diagnose your situation.

      The solution is to not quote variables when you don't need it. Remove the double quotes:

      my $dbh = $_[0];

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        Corion: The error was Can't locate object method "prepare" via package "DBI::db=HASH(0x215bc78)" (perhaps you forgot to load "DBI::db=HASH(0x215bc78)"?)

        Fletch and Corion:

        You are right. When I removed the quotes (leaving only my $dbh = $_[0];), it works as expected.

        Anyway, what exactly does ‘The solution is to not quote variables when you don't need it.’ mean? That I should quote only strings?

        Thank you both!

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      You've stringified all three of your arguments which isn't what you want to do. A DBI handle is an object which is (usually) implemented as a reference to a data structure such as a hash. When you pass it through double quotes you're breaking that reference (hand waving a bit here; see perlobj for more details) so when you try and call methods upon it you're trying to call methods on a string value (hence your error).

      The cake is a lie.
      The cake is a lie.
      The cake is a lie.

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