Order to paint in one level

[Salvador Vidal]

In a Polygon Layer of PostGis with diferent Class,

What class paint above what.
Paint in order Class?

Paint in order query?, if this, if i put a order, it's posible paint on
order.

Explain, i have a table with diferent zones, example, green, water,
street, etc. all in the same table.

I can make diferent level's. OK
but y a want to make 1 level (is one table) it's possible?

Thanks