File Coverage

blib/lib/Class/DBI/Pg.pm

Criterion	Covered	Total	%
statement	9	54	16.6
branch	0	20	0.0
condition			n/a
subroutine	3	5	60.0
pod	2	2	100.0
total	14	81	17.2

package Class::DBI::Pg;

use strict;
require Class::DBI;
use base 'Class::DBI';
use vars qw($VERSION);

$VERSION = '0.08';

sub set_up_table {
    my ( $class, $table ) = @_;
    my $dbh     = $class->db_Main;
    my $catalog = "";
    if ( $class->pg_version >= 7.3 ) {
        $catalog = 'pg_catalog.';
    }

    # find primary key
    my $sth = $dbh->prepare(<<"SQL");
SELECT indkey FROM ${catalog}pg_index
WHERE indisprimary=true AND indrelid=(
SELECT oid FROM ${catalog}pg_class
WHERE relname = ?)
SQL
    $sth->execute($table);
    my %prinum = map { $_ => 1 } split ' ', $sth->fetchrow_array;
    $sth->finish;

    # find all columns
    $sth = $dbh->prepare(<<"SQL");
SELECT a.attname, a.attnum
FROM ${catalog}pg_class c, ${catalog}pg_attribute a
WHERE c.relname = ?
  AND a.attnum > 0 AND a.attrelid = c.oid
ORDER BY a.attnum
SQL
    $sth->execute($table);
    my $columns = $sth->fetchall_arrayref;
    $sth->finish;

    # find SERIAL type.
    # nextval('"table_id_seq"'::text)
    $sth = $dbh->prepare(<<"SQL");
SELECT adsrc FROM ${catalog}pg_attrdef
WHERE
adrelid=(SELECT oid FROM ${catalog}pg_class WHERE relname=?)
SQL
    $sth->execute($table);
    my ($nextval_str) = $sth->fetchrow_array;
    $sth->finish;

    # the text representation for nextval() changed between 7.x and 8.x
    my $sequence;
    if ($nextval_str) {
        if ($class->pg_version() >= 8.1) {
            # hackish, but oh well...
            ($sequence) =
                $nextval_str =~ m!^nextval\('"?([^"']+)"?'::regclass\)!i ?
                    $1 :
                $nextval_str =~ m!^nextval\(\("?([^"']+)"?'::text\)?::regclass\)!i ?
                    $1 :
                undef;
        } else {
            ($sequence) = $nextval_str =~ m!^nextval\('"?([^"']+)"?'::text\)!;
        }
    }

    my ( @cols, @primary );
    foreach my $col (@$columns) {
        # skip dropped column.
        next if $col->[0] =~ /^\.+pg\.dropped\.\d+\.+$/;
        push @cols, $col->[0];
        next unless $prinum{ $col->[1] };
        push @primary, $col->[0];
    }
    if (!@primary) {
        require Carp;
        Carp::croak("$table has no primary key");
    }
    $class->table($table);
    $class->columns( Primary => @primary );
    $class->columns( All     => @cols );
    $class->sequence($sequence) if $sequence;
}

sub pg_version {
    my $class = shift;
    my %args  = @_;

    my $dbh   = $class->db_Main;
    my $sth   = $dbh->prepare("SELECT version()");
    $sth->execute;
    my ($ver_str) = $sth->fetchrow_array;
    $sth->finish;
    my ($ver) =
        $args{full_version} ?
            $ver_str =~ m/^PostgreSQL ([\d\.]{5})/ :
            $ver_str =~ m/^PostgreSQL ([\d\.]{3})/;
    return $ver;
}

__END__