sql select mod

sql.pl

use strict;
use warnings;
use Data::Dump 'dd';

sub query (@) {
    my ($in, $p, $o, $l) = @_;
    (join' ', $in, map @$_, grep $_->[1],
         $p ? [where => join ' and ', map $_.' = ?', keys%$p] : (),
         $o ? ['order by' => join ',', @$o] : (),
         $l ? [limit => join ',', ('?') x @$l] : ()),
    $p ? values%$p : (), $l ? @$l : () }

sub fetch (@) {
    my ($dbh, $q, @p) = @_;
    $dbh->selectall_arrayref($q, {}, @p) }

dd query 'select i from t', {qw(a 1 b 2)}, ['id desc','a asc'], [0,1];
# fetch $dbh, query 'select i from t', {qw(a 1 b 2)}, ['id desc','a asc'], [0,1];
dd query 'select i from t', {qw(a 1 b 2)}, undef, [0];
dd query 'select i from t', {}, ['a'], [];
dd query 'select i from t', (undef)x2, [1];