Oracle PL/SQL/Cursor/Reference Cursor — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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Версия 13:45, 26 мая 2010
Содержание
- 1 Define and use reference cursor
- 2 Defines and declares a reference cursor before explicitly opening it
- 3 REF CURSOR custom type
- 4 refcursor variable
- 5 Reference cursor demo
- 6 Reference value in a cursor by cursor variable
- 7 Set the REFCURSOR variable to the results of a SELECT statement, and print out the REFCURSOR variable
Define and use reference cursor
SQL> -- Define and use reference cursor
SQL>
SQL> create table myTable as select * from all_users;
Table created.
SQL>
SQL> variable myReferenceCursor refcursor;
SQL>
SQL> begin
2 open :myReferenceCursor for select * from myTable;
3 end;
4 /
PL/SQL procedure successfully completed.
SQL>
SQL> delete from myTable;
14 rows deleted.
SQL>
SQL> commit;
Commit complete.
SQL>
SQL> print myReferenceCursor;
USERNAME USER_ID CREATED
------------------------------ ---------- ---------
BOB 36 30-AUG-06
FLOWS_020100 35 07-FEB-06
FLOWS_FILES 34 07-FEB-06
HR 33 07-FEB-06
MDSYS 32 07-FEB-06
ANONYMOUS 28 07-FEB-06
XDB 27 07-FEB-06
CTXSYS 25 07-FEB-06
DBSNMP 23 07-FEB-06
TSMSYS 20 07-FEB-06
DIP 18 07-FEB-06
USERNAME USER_ID CREATED
------------------------------ ---------- ---------
OUTLN 11 07-FEB-06
SYSTEM 5 07-FEB-06
SYS 0 07-FEB-06
14 rows selected.
SQL>
SQL>
SQL> drop table myTable;
Table dropped.
SQL>
SQL>
Defines and declares a reference cursor before explicitly opening it
SQL>
SQL> DECLARE
2 TYPE weakly_typed IS REF CURSOR;
3 quick WEAKLY_TYPED;
4 BEGIN
5 OPEN quick FOR
6 SELECT item_title
7 , COUNT(*)
8 FROM item
9 HAVING (COUNT(*) > 2)
10 GROUP BY item_title;
11 :refcur := quick;
12 END;
13 /
SP2-0552: Bind variable "REFCUR" not declared.
SQL>
REF CURSOR custom type
SQL> CREATE TABLE book (
2 isbn CHAR(10) PRIMARY KEY,
3 category VARCHAR2(20),
4 title VARCHAR2(100),
5 num_pages NUMBER,
6 price NUMBER,
7 copyright NUMBER(4),
8 emp1 NUMBER,
9 emp2 NUMBER,
10 emp3 NUMBER
11 );
Table created.
SQL>
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2, emp3)
2 VALUES ("1", "Database", "Oracle", 563, 39.99, 2009, 1, 2, 3);
1 row created.
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2)
2 VALUES ("2", "Database", "MySQL", 765, 44.99, 2009, 4, 5);
1 row created.
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2, emp3)
2 VALUES ("3", "Database", "SQL Server", 404, 39.99, 2001, 6, 7, 8);
1 row created.
SQL>
SQL>
SQL> SET SERVEROUTPUT ON ESCAPE OFF
SQL>
SQL> DECLARE
2
3 TYPE book_typ IS REF CURSOR RETURN book%ROWTYPE;
4 cv_book book_typ;
5 v_book book%ROWTYPE;
6
7 BEGIN
8
9 DBMS_OUTPUT.ENABLE(1000000);
10
11 OPEN cv_book FOR SELECT * FROM book WHERE isbn = "1";
12
13 FETCH cv_book INTO v_book;
14
15 DBMS_OUTPUT.PUT_LINE(v_book.title||" is "||v_book.price);
16
17 CLOSE cv_book;
18 END;
19 /
Oracle is 39.99
PL/SQL procedure successfully completed.
SQL>
SQL> drop table book;
Table dropped.
refcursor variable
SQL>
SQL> create table t as select * from all_users;
Table created.
SQL>
SQL> variable x refcursor
SQL>
SQL> begin
2 open :x for select * from t;
3 end;
4 /
PL/SQL procedure successfully completed.
SQL>
SQL> delete from t;
27 rows deleted.
SQL>
SQL> commit;
Commit complete.
SQL>
SQL> print x
USERNAME USER_ID CREATED
------------------------------ ---------- ---------
SYS 0 07-FEB-06
SYSTEM 5 07-FEB-06
OUTLN 11 07-FEB-06
DIP 18 07-FEB-06
TSMSYS 20 07-FEB-06
INV15 42 17-OCT-09
DBSNMP 23 07-FEB-06
INV10 37 17-OCT-09
CTXSYS 25 07-FEB-06
XDB 27 07-FEB-06
ANONYMOUS 28 07-FEB-06
MDSYS 32 07-FEB-06
HR 33 07-FEB-06
FLOWS_FILES 34 07-FEB-06
FLOWS_020100 35 07-FEB-06
sqle 36 15-OCT-09
INV11 38 17-OCT-09
INV12 39 17-OCT-09
INV13 40 17-OCT-09
INV14 41 17-OCT-09
PLSQL 57 19-OCT-09
INV16 43 17-OCT-09
INV17 44 17-OCT-09
INV18 45 17-OCT-09
INV19 46 17-OCT-09
INV20 47 17-OCT-09
DEFINER 48 17-OCT-09
27 rows selected.
SQL>
SQL> drop table t;
Table dropped.
Reference cursor demo
SQL>
SQL> CREATE TABLE emp (
2 id NUMBER PRIMARY KEY,
3 fname VARCHAR2(50),
4 lname VARCHAR2(50)
5 );
Table created.
SQL>
SQL> INSERT INTO emp (id, fname, lname)VALUES (1, "A", "B");
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (2, "C", "D");
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (3, "Enn", "F");
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (4, "G", "H");
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (5, "G", "Z");
1 row created.
SQL>
SQL>
SQL> SET SERVEROUTPUT ON ESCAPE OFF
SQL>
SQL> CREATE OR REPLACE PROCEDURE emp_sel (cv_results IN OUT SYS_REFCURSOR)
2 IS
3 BEGIN
4 OPEN cv_results FOR SELECT id, fname, lname FROM emp;
5 END;
6 /
Procedure created.
SQL>
SQL> VARIABLE x REFCURSOR
SQL>
SQL> EXEC emp_sel(:x)
PL/SQL procedure successfully completed.
SQL>
SQL> print x
ID FNAME
---------- --------------------------------------------------
LNAME
--------------------------------------------------
1 A
B
2 C
D
3 Enn
F
4 G
H
5 G
Z
5 rows selected.
SQL>
SQL> drop table emp;
Table dropped.
SQL>
Reference value in a cursor by cursor variable
SQL>
SQL> -- create demo table
SQL> create table emp(
2 ID VARCHAR2(4 BYTE) NOT NULL,
3 fname VARCHAR2(10 BYTE),
4 lname VARCHAR2(10 BYTE),
5 Start_Date DATE,
6 End_Date DATE,
7 Salary Number(8,2),
8 City VARCHAR2(10 BYTE),
9 Description VARCHAR2(15 BYTE)
10 )
11 /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values ("01","Jason", "Martin", to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto", "Programmer")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("02","Alison", "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("03","James", "Smith", to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("04","Celia", "Rice", to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("05","Robert", "Black", to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("06","Linda", "Green", to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York", "Tester")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("07","David", "Larry", to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York", "Manager")
3 /
1 row created.
SQL> insert into emp(ID, fname, lname, Start_Date, End_Date, Salary, City, Description)
2 values("08","James", "Cat", to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
3 /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from emp
2 /
ID FNAME LNAME START_DAT END_DATE SALARY CITY
---- ---------- ---------- --------- --------- ---------- ----------
DESCRIPTION
---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56 Toronto
Programmer
02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver
Tester
03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver
Tester
ID FNAME LNAME START_DAT END_DATE SALARY CITY
---- ---------- ---------- --------- --------- ---------- ----------
DESCRIPTION
---------------
04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver
Manager
05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver
Tester
06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York
Tester
ID FNAME LNAME START_DAT END_DATE SALARY CITY
---- ---------- ---------- --------- --------- ---------- ----------
DESCRIPTION
---------------
07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York
Manager
08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver
Tester
8 rows selected.
SQL> CREATE OR REPLACE PROCEDURE myProcedure
2 AS
3 CURSOR myCursor IS SELECT id, fname FROM emp;
4 TYPE firstNameType IS TABLE OF emp.fname%type INDEX BY emp.id%type;
5 ch firstNameType;
6 i integer := 0;
7 imax integer;
8 BEGIN
9 FOR j IN myCursor LOOP
10 i := i + 1;
11 ch(i) := j.fname;
12 END LOOP;
13 dbms_output.put_line(ch("James"));
14 END myProcedure;
15 /
Procedure created.
SQL>
SQL> exec myProcedure;
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table emp
2 /
Table dropped.
SQL>
SQL>
SQL>
Set the REFCURSOR variable to the results of a SELECT statement, and print out the REFCURSOR variable
SQL>
SQL> SET ECHO OFF
SQL>
SQL> VARIABLE l_table_list REFCURSOR
SQL>
SQL>
SQL> BEGIN
2 OPEN :l_table_list FOR
3 SELECT table_name FROM user_tables;
4 END;
5 /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> PRINT l_table_list
COURSE
EMP_AUDIT
MYTABLE1
MYLOG
P
SYSTEM_STATS
INVENTORY_TBL
DEPT$AUDIT
PASSWORD_AUDIT
EMP_DELTAS
CUSTLOG
DEMO
CUST_NO_KEY_TABLE
IT
P1
MYSTATS
WORKING_EMPS
WORKING_EMPLOYEES
EMPTEMPTABLE
TEMP_TABLE
EMPLOYEETEMPTABLE
TMP
PARMS
IX
CUST_WITH_VARRAY_TEMP_TABLE
WORKING_CUSTOMERS
26 rows selected.
SQL>
SQL>
SQL>