Oracle PL/SQL Tutorial/Date Timestamp Functions/NEXT DAY

Finding the First Monday in the Month of August

SQL> SELECT TO_CHAR(NEXT_DAY("01-AUG-99","Monday"),"MM/DD/YYYY HH:MM:SS AM")
  2       "Next_Day"
  3  from DUAL;
Next_Day
----------------------
08/02/1999 12:08:00 AM
SQL>

Finding the First Monday in the Month of September

SQL> SELECT TO_CHAR(NEXT_DAY("01-SEP-99","Monday"),"MM/DD/YYYY HH:MM:SS AM")
  2       "Next_Day"
  3   from DUAL;
Next_Day
----------------------
09/06/1999 12:09:00 AM
SQL>

NEXT_DAY function

The NEXT_DAY function returns the date of the day of the week following a particular date.

"day of the week" is expressed as the day written out (like Monday, Tuesday, etc.).

SQL>
SQL> SELECT NEXT_DAY(TO_DATE("15SEP2006","DDMONYYYY"),"Monday") FROM dual;
NEXT_DAY(
---------
18-SEP-06

NEXT_DAY(start_date-1,"Tuesday")

SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  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("20060
725","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("19860
221","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("19900
315","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("19990
421","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("19980
808","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("19960
104","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("19980
212","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("20020
415","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> SELECT start_date, NEXT_DAY(start_date-1,"Tuesday")
  2  FROM employee;
START_DAT NEXT_DAY(
--------- ---------
25-JUL-96 30-JUL-96
21-MAR-76 23-MAR-76
12-DEC-78 12-DEC-78
24-OCT-82 26-OCT-82
15-JAN-84 17-JAN-84
30-JUL-87 04-AUG-87
31-DEC-90 01-JAN-91
17-SEP-96 17-SEP-96
8 rows selected.
SQL>
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>

next_day(sysdate,"SAT")

SQL>
SQL> select sysdate
  2  ,      next_day(sysdate,"SAT") as next_sat
  3  from   dual;
SYSDATE   NEXT_SAT
--------- ---------
24-JUL-08 26-JUL-08
SQL>

NEXT_DAY(x, day): get the date of the next day following x;

You specify day as a literal string, such as SATURDAY.

Displays the date of the next Saturday after January 1, 2005:

SQL> SELECT NEXT_DAY("01-JAN-2005", "SATURDAY") FROM dual;
NEXT_DAY(
---------
08-JAN-05
SQL>

The Proper Method to Find the First Monday in a Given Month

SQL> SELECT TO_CHAR(NEXT_DAY("31-AUG-99","Monday"),"MM/DD/YYYY HH:MM:SS AM")
  2       "Next_Day"
  3   from DUAL;
Next_Day
----------------------
09/06/1999 12:09:00 AM
SQL>
SQL>