Collection Methods (Built-ins)
PL/SQL offers a number of built-in functions and procedures, known as collection methods, that let you obtain information about and modify the contents of collections. Table 12-3 contains the complete list of these programs.
Table 12-3. Collection methods
Method (function or procedure)
Returns the current number of elements in a collection.
Removes one or more elements from the collection. Reduces COUNT if the element is not already removed. With VARRAYs, you can delete only the entire contents of the collection.
Returns TRUE or FALSE to indicate whether the specified element exists.
Increases the number of elements in a nested table or VARRAY. Increases COUNT.
FIRST, LAST functions
Returns the smallest (FIRST) and largest (LAST) subscript in use.
Returns the maximum number of elements allowed in a VARRAY.
PRIOR, NEXT functions
Returns the subscript immediately before (PRIOR) or after (NEXT) a specified subscript. You should always use PRIOR and NEXT to traverse a collection, especially if you are working with sparse (or potentially sparse) collections.
Removes collection elements from the end of the collection (highest defined subscript).
These programs are referred to as methods because the syntax for using the collection built-ins is different from the normal syntax used to call procedures and functions. Collection methods employ a member method syntax that’s ...