Oracle PL/SQL Tutorial/Collections/MEMBER OF
Версия от 13:45, 26 мая 2010; (обсуждение)
Содержание
MEMBER OF is a logical comparison operator
SQL>
SQL> DECLARE
2 TYPE list IS TABLE OF NUMBER;
3 n VARCHAR2(10) := "One";
4 a LIST := list("One", "Two", "Three");
5 BEGIN
6 IF n MEMBER OF a THEN
7 dbms_output.put_line(""n" is member.");
8 END IF;
9 END;
10 /
DECLARE
*
ERROR at line 1:
ORA-06502: PL/SQL: numeric or value error: character to number conversion error
ORA-06512: at line 4
MEMBER OF Operator
MEMBER OF operator checks whether an element is in a nested table.
SQL> CREATE OR REPLACE PROCEDURE member_of_example AS
2 TYPE nestedTableType IS TABLE OF VARCHAR2(10);
3 myTable1 nestedTableType;
4 result BOOLEAN;
5 BEGIN
6 myTable1 := nestedTableType("F", "G", "S");
7 result := "George" MEMBER OF myTable1;
8 IF result THEN
9 DBMS_OUTPUT.PUT_LINE("""George"" is a member");
10 END IF;
11 END member_of_example;
12 /
Procedure created.
SQL> CALL member_of_example();
Call completed.
SQL>
SQL>
MEMBER OF operator finds if the left operand is a member of the collection used as the right operand
SQL> CREATE OR REPLACE TYPE list IS TABLE OF NUMBER;
2 /
Type created.
SQL>
SQL> CREATE OR REPLACE FUNCTION format_list(set_in LIST) RETURN VARCHAR2 IS
2 returnValue VARCHAR2(2000);
3 BEGIN
4
5 FOR i IN set_in.FIRST..set_in.LAST LOOP
6 returnValue := set_in(i)||" ";
7 END LOOP;
8 RETURN returnValue;
9 END format_list;
10 /
Function created.
SQL>
SQL> DECLARE
2 n VARCHAR2(10) := "One";
3 a LIST := list("One","Two","Three");
4 BEGIN
5 IF n MEMBER OF a THEN
6 dbms_output.put_line(""n" is member.");
7 END IF;
8 END;
9 /
DECLARE
*
ERROR at line 1:
ORA-06502: PL/SQL: numeric or value error: character to number conversion error
ORA-06512: at line 3
SQL>
MEMBER OF table collection
SQL> CREATE OR REPLACE PROCEDURE member_of_example AS
2 TYPE charTable IS TABLE OF VARCHAR2(10);
3 emp1 charTable;
4 result BOOLEAN;
5 BEGIN
6 emp1 := charTable("A", "B", "C");
7 result := "A" MEMBER OF emp1;
8 IF result THEN
9 DBMS_OUTPUT.PUT_LINE("""A"" is a member");
10 END IF;
11 END member_of_example;
12 /
Procedure created.