Oracle PL/SQL Tutorial/PL SQL Data Types/Date Type Convert
Содержание
Assign that date variable to another string
<source lang="sql">
SQL> SQL> SET ECHO ON SQL> SET SERVEROUTPUT ON SQL> DECLARE
2 d1 DATE;
3 cd1 VARCHAR2(10);
4 cd2 VARCHAR2(10);
5 n1 NUMBER;
6 cn1 VARCHAR2(10);
7 cn2 VARCHAR2(10);
8 BEGIN
9 cd1 := "15-Nov-61";
10 d1 := cd1;
11
12 cd2 := d1;
13
14 DBMS_OUTPUT.PUT_LINE("CD1 = " || cd1);
15 DBMS_OUTPUT.PUT_LINE("d1 = " || d1);
16 DBMS_OUTPUT.PUT_LINE("CD2 = " || cd2);
17
18 END;
19 /
CD1 = 15-Nov-61 d1 = 15-NOV-61 CD2 = 15-NOV-61 PL/SQL procedure successfully completed.</source>
Assign the string to a date variable. The conversion is implicit.
<source lang="sql">
SQL> SQL> SET ECHO ON SQL> SET SERVEROUTPUT ON SQL> DECLARE
2 d1 DATE;
3 cd1 VARCHAR2(10);
4 cd2 VARCHAR2(10);
5 n1 NUMBER;
6 cn1 VARCHAR2(10);
7 cn2 VARCHAR2(10);
8 BEGIN
9 cd1 := "15-Nov-61";
10
11 d1 := cd1;
12 DBMS_OUTPUT.PUT_LINE("CD1 = " || cd1);
13 DBMS_OUTPUT.PUT_LINE("d1 = " || d1);
14
15 END;
16 /
CD1 = 15-Nov-61 d1 = 15-NOV-61 PL/SQL procedure successfully completed. SQL> SQL></source>
Determine and display years and months
<source lang="sql">
SQL> SQL> DECLARE
2 start_date DATE; 3 end_date DATE; 4 service_interval INTERVAL YEAR TO MONTH; 5 years_of_service NUMBER; 6 months_of_service NUMBER; 7 BEGIN 8 service_interval := (end_date - start_date) YEAR TO MONTH; 9 DBMS_OUTPUT.PUT_LINE(service_interval); 10 11 END; 12 /
PL/SQL procedure successfully completed.</source>
Explicit declaration of format mask
<source lang="sql">
SQL> SQL> declare
2 v_temp_dt DATE;
3 v_count_nr NUMBER(10);
4 begin
5
6 -- Explicit declaration of format mask.
7 v_temp_dt := to_DATE("01-JAN-2007","dd-mon-yyyy");
8
9 end;
10 /
PL/SQL procedure successfully completed. SQL></source>
Explicit declaration of format mask in where clause
<source lang="sql">
SQL> SQL> SQL> SQL> -- create demo table SQL> create table Employee(
2 ID VARCHAR2(4 BYTE) NOT NULL primary key, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee(ID, First_Name, Last_Name, 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 Employee
2 /
ID FIRST_NAME LAST_NAME 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 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 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> SQL> SQL> SQL> SQL> declare
2 v_temp_dt DATE;
3 v_count_nr NUMBER(10);
4 begin
5 -- Explicit declaration of format mask in where clause.
6 select count(*) into v_count_nr
7 from employee
8 where start_date < to_DATE("01-JAN-2001","dd-mon-yyyy");
9 end;
10 /
PL/SQL procedure successfully completed. SQL> SQL> SQL> SQL> -- clean the table SQL> drop table Employee
2 /
Table dropped.</source>
Use TO_CHAR in PL/SQL
<source lang="sql">
SQL> SQL> SET ECHO ON SQL> SQL> SET SERVEROUTPUT ON SQL> DECLARE
2 payment_due_date DATE;
3 BEGIN
4 payment_due_date := TRUNC(SYSDATE);
5
6 DBMS_OUTPUT.PUT_LINE("Today is " || TO_CHAR(SYSDATE,"dd-Mon-yyyy"));
7 DBMS_OUTPUT.PUT_LINE("Payment is due on " || TO_CHAR(payment_due_date,"dd-Mon-yyyy"));
8
9 END;
10 /
Today is 02-Jun-2007 Payment is due on 02-Jun-2007 PL/SQL procedure successfully completed. SQL> SQL></source>
