Updating the records in to the cursor
This makes nested tables suitable for queries and updates that only affect some elements of the collection.
You cannot rely on the order and subscripts of a nested table remaining stable as the table is stored and retrieved, because the order and subscripts are not preserved when a nested table is stored in the database.
You can define collection types in a procedure, function, or package.
You can pass collection variables as parameters, to move data between client-side applications and stored subprograms.
To create collections, you define a collection type, then declare variables of that type.
You can define types in the declarative part of any PL/SQL block, subprogram, or package.
In this chapter, you learn how those types let you reference and manipulate collections of data as whole objects.
You also learn how the datatype is an ordered group of elements, all of the same type.
You can model multi-dimensional arrays by creating nested tables whose elements are also nested tables.Associative arrays are appropriate for relatively small lookup tables where the collection can be constructed in memory each time a procedure is called or a package is initialized.