MAX_CARDINALITY
The MAX_CARDINALITY function returns a value representing the maximum number of elements an array can contain. This is the cardinality specified on the CREATE TYPE (Array) statement for the user-defined array type.
- array-expression
- The expression can be either an SQL variable or parameter of an array data type, or a cast specification of a parameter marker to an array data type.
The result of the function is BIGINT. The result cannot be null.
Example
Assume that array type PHONENUMBERS and array variable RECENT_CALLS are defined as follows:
CREATE TYPE PHONENUMBERS AS INTEGER ARRAY[50];
DECLARE RECENT_CALLS PHONENUMBERS;
The following statement
sets LIST_SIZE to the maximum cardinality with which RECENT_CALLS
was defined.
SET LIST_SIZE = MAX_CARDINALITY(RECENT_CALLS)
After the statement executes, LIST_SIZE contains 50.