well here is not php, but... it's a criticism...before this query, did you checked that $_POST[*] are double or int values? if they are string, maybe you can have sql injection in your app...
well if it's php here is one example what i'm talking about...
$_POST['MovsDelAno']=(int)$_POST['MovsDelAno'];
$_POST['MovsDelMes']=(int)$_POST['MovsDelMes'];
$_POST['MovsDelDia']=(int)$_POST['MovsDelDia'];
$_POST['MovsAlAno']=(int)$_POST['MovsAlAno'];
$_POST['MovsAlMes']=(int)$_POST['MovsAlMes'];
$_POST['MovsAlDia']=(int)$_POST['MovsAlDia'];
// now concat your strings...
$SQL="select sum( CantidadPedida ) as SumPedida,
sum( CantidadRecibida ) as SumRecibida,
ArticuloCodigo, ArticuloNombre, ArticuloCosto,
ArticulosDisponibles, ArticuloUnidad
from ArticulosPedidos
inner join PedidosIndex on
PedidosIndex.NumDePedido = ArticulosPedidos.NumDePedido
inner join CatArticulos on
ArticulosPedidos.ArticuloID = CatArticulos.ArticuloID
where ArticulosPedidos.Fecha between
'{$_POST['MovsDelAno']}-{$_POST['MovsDelMes']}-{$_POST['MovsDelDia']}' and
'{$_POST['MovsAlAno']}-{$_POST['MovsAlMes']}-{$_POST['MovsAlDia']}'
group by ArticulosPedidos.ArticuloID
order by SumPedida DESC limit 500"
about what this query do, i don't know... but from mysq