A birdcage (or bird cage) is a cage designed to house birds as pets. Antique (or antique-style) birdcages are often popular as collectors' items or as household decor but most are not suitable for housing live birds, being too small, or of unsafe materials or construction.ood quality cages designed for pet birds are more suitable. Most parrot cages are made or wrought iron and painted with a non-toxic paint referred to as powder-coating. However, the newest trend in the market is cages made of solid stainless steel.
A viewport is a 2D rectangle that defines the size of the rendering surface onto which a 3D scene is projected.
A view cluster is a group of maintenance dialogs, which are collected in one maintenance unit for business or technical reasons. We can arrange the data in a hierarchical or non-hierarchical manner. A view cluster consists of different objects, which can be tables, views.