Date/Time Functions and Operators

Date and Time Operators

WARNING: When the user uses date and time operators, explicit type prefixes are modified for corresponding operands to ensure that the operands parsed by the database are consistent with what the user expects, and no unexpected results occur. For example, abnormal mistakes will occur in the following example without an explicit data type.

SELECT date '2001-10-01' - '7' AS RESULT;

Table 1 Time and date operators

Operator

Example

+

openGauss=# SELECT date '2001-9-28' + integer '7' AS RESULT;
   result
------------
 2001-10-05
(1 row)
openGauss=# SELECT date '2001-09-28' + interval '1 hour' AS RESULT;
       result        
---------------------
 2001-09-28 01:00:00
(1 row)
openGauss=# SELECT date '2001-09-28' + time '03:00' AS RESULT;
       result        
---------------------
 2001-09-28 03:00:00
(1 row)
openGauss=# SELECT interval '1 day' + interval '1 hour' AS RESULT;
     result     
----------------
 1 day 01:00:00
(1 row)
openGauss=# SELECT timestamp '2001-09-28 01:00' + interval '23 hours' AS RESULT;
       result        
---------------------
 2001-09-29 00:00:00
(1 row)
openGauss=# SELECT time '01:00' + interval '3 hours' AS RESULT;
  result  
----------
 04:00:00
(1 row)

-

openGauss=# SELECT date '2001-10-01' - date '2001-09-28' AS RESULT;
 result
--------
 3 days
(1 row)
openGauss=# SELECT date '2001-10-01' - integer '7' AS RESULT;
       result        
---------------------
 2001-09-24 00:00:00
(1 row)
openGauss=# SELECT date '2001-09-28' - interval '1 hour' AS RESULT;
       result        
---------------------
 2001-09-27 23:00:00
(1 row)
openGauss=# SELECT time '05:00' - time '03:00' AS RESULT;
  result  
----------
 02:00:00
(1 row)
openGauss=# SELECT time '05:00' - interval '2 hours' AS RESULT;
  result  
----------
 03:00:00
(1 row)
openGauss=# SELECT timestamp '2001-09-28 23:00' - interval '23 hours' AS RESULT;
       result        
---------------------
 2001-09-28 00:00:00
(1 row)
openGauss=# SELECT interval '1 day' - interval '1 hour' AS RESULT;
  result  
----------
 23:00:00
(1 row)
openGauss=# SELECT timestamp '2001-09-29 03:00' - timestamp '2001-09-27 12:00' AS RESULT;
     result     
----------------
 1 day 15:00:00
(1 row)

*

openGauss=# SELECT 900 * interval '1 second' AS RESULT;
  result  
----------
 00:15:00
(1 row)
openGauss=# SELECT 21 * interval '1 day' AS RESULT;
 result  
---------
 21 days
(1 row)
openGauss=# SELECT double precision '3.5' * interval '1 hour' AS RESULT;
  result  
----------
 03:30:00
(1 row)

/

openGauss=# SELECT interval '1 hour' / double precision '1.5' AS RESULT;
  result  
----------
 00:40:00
(1 row)

Time and Date Functions

  • age(timestamp, timestamp)

    Description: Subtracts parameters, producing a result in YYYY-MM-DD format. If the result is negative, the returned result is also negative. The input parameters can contain a time zone or not.

    Return type: interval

    Example:

    openGauss=# SELECT age(timestamp '2001-04-10', timestamp '1957-06-13');
               age           
    -------------------------
     43 years 9 mons 27 days
    (1 row)
    
  • age(timestamp)

    Description: Minuses the current time with the parameter. The input parameter can contain a time zone or not.

    Return type: interval

    Example:

    openGauss=# SELECT age(timestamp '1957-06-13');
               age           
    -------------------------
     60 years 2 mons 18 days
    (1 row)
    
  • clock_timestamp()

    Description: Specifies the current timestamp of the real-time clock.

    Return type: timestamp with time zone

    Example:

    openGauss=# SELECT clock_timestamp();
            clock_timestamp        
    -------------------------------
     2017-09-01 16:57:36.636205+08
    (1 row)
    
  • current_date

    Description: Specifies the current date.

    Return type: date

    Example:

    openGauss=# SELECT current_date;
        date    
    ------------
     2017-09-01
    (1 row)
    
  • current_time

    Description: Specifies the current time.

    Return type: time with time zone

    Example:

    openGauss=# SELECT current_time;
           timetz       
    --------------------
     16:58:07.086215+08
    (1 row)
    
  • current_timestamp

    Description: Specifies the current date and time.

    Return type: timestamp with time zone

    Example:

    openGauss=# SELECT current_timestamp;
           pg_systimestamp        
    ------------------------------
     2017-09-01 16:58:19.22173+08
    (1 row)
    
  • date_part(text, timestamp)

    Description: Obtains the value of a subcolumn in the date or time value, for example, the year or hour. It is equivalent to extract(field from timestamp).

    Timestamp type: abstime, date, interval, reltime, time with time zone, time without time zone, timestamp with time zone, timestamp without time zone

    Return type: double precision

    Example:

    openGauss=# SELECT date_part('hour', timestamp '2001-02-16 20:38:40');
     date_part 
    -----------
            20
    (1 row)
    
  • date_part(text, interval)

    Description: Obtains the value of a subcolumn in the date or time value. When obtaining the month value, if the value is greater than 12, obtain the remainder after it is divided by 12. It is equivalent to extract(field from timestamp).

    Return type: double precision

    Example:

    openGauss=# SELECT date_part('month', interval '2 years 3 months');
     date_part 
    -----------
             3
    (1 row)
    
  • date_trunc(text, timestamp)

    Description: Truncates to the precision specified by text.

    Return type: interval, timestamp with time zone, timestamp without time zone

    Example:

    openGauss=# SELECT date_trunc('hour', timestamp  '2001-02-16 20:38:40');
         date_trunc      
    ---------------------
     2001-02-16 20:00:00
    (1 row)
    
  • trunc(timestamp)

    Description: Truncates to day by default.

    Example:

    openGauss=# SELECT trunc(timestamp  '2001-02-16 20:38:40');                                                                                                                                                                   trunc
    ---------------------
    2001-02-16 00:00:00
    (1 row)
    
  • daterange(arg1, arg2)

    Description: Obtains time boundary information. The type of arg1 and arg2 is date.

    Return type: daterange

    Example:

    openGauss=# select daterange('2000-05-06','2000-08-08');
            daterange        
    -------------------------
     [2000-05-06,2000-08-08)
    (1 row)
    
  • extract(field from timestamp)

    Description: Obtains the hour.

    Return type: double precision

    Example:

    openGauss=# SELECT extract(hour from timestamp '2001-02-16 20:38:40');
     date_part 
    -----------
            20
    (1 row)
    
  • extract(field from interval)

    Description: Obtains the month. If the value is greater than 12, obtain the remainder after it is divided by 12.

    Return type: double precision

    Example:

    openGauss=# SELECT extract(month from interval '2 years 3 months');
     date_part 
    -----------
             3
    (1 row)
    
  • isfinite(date)

    Description: Tests for a valid date.

    Return type: Boolean

    Example:

    openGauss=# SELECT isfinite(date '2001-02-16');
     isfinite 
    ----------
     t
    (1 row)
    
  • isfinite(timestamp)

    Description: Tests for a valid timestamp.

    Return type: Boolean

    Example:

    openGauss=# SELECT isfinite(timestamp '2001-02-16 21:28:30');
     isfinite 
    ----------
     t
    (1 row)
    
  • isfinite(interval)

    Description: Tests for a valid interval.

    Return type: Boolean

    Example:

    openGauss=# SELECT isfinite(interval '4 hours');
     isfinite 
    ----------
     t
    (1 row)
    
  • justify_days(interval)

    Description: Adjusts intervals to 30-day time periods, which are represented as months.

    Return type: interval

    Example:

    openGauss=# SELECT justify_days(interval '35 days');
     justify_days 
    --------------
     1 mon 5 days
    (1 row)
    
  • justify_hours(interval)

    Description: Sets the time interval in days (24 hours is one day).

    Return type: interval

    Example:

    openGauss=# SELECT JUSTIFY_HOURS(INTERVAL '27 HOURS');
     justify_hours  
    ----------------
     1 day 03:00:00
    (1 row)
    
  • justify_interval(interval)

    Description: Adjusts interval using justify_days and justify_hours.

    Return type: interval

    Example:

    openGauss=# SELECT JUSTIFY_INTERVAL(INTERVAL '1 MON -1 HOUR');
     justify_interval 
    ------------------
     29 days 23:00:00
    (1 row)
    
  • localtime

    Description: Specifies the current time.

    Return type: time

    Example:

    openGauss=# SELECT localtime AS RESULT;
         result
    ----------------
     16:05:55.664681
    (1 row)
    
  • localtimestamp

    Description: Specifies the current date and time.

    Return type: timestamp

    Example:

    openGauss=# SELECT localtimestamp;
             timestamp          
    ----------------------------
     2017-09-01 17:03:30.781902
    (1 row)
    
  • now()

    Description: Specifies the current date and time.

    Return type: timestamp with time zone

    Example:

    openGauss=# SELECT now();
                  now              
    -------------------------------
     2017-09-01 17:03:42.549426+08
    (1 row)
    
  • timenow

    Description: Specifies the current date and time.

    Return type: timestamp with time zone

    Example:

    openGauss=# select timenow();
            timenow
    ------------------------
     2020-06-23 20:36:56+08
    (1 row)
    
  • numtodsinterval(num, interval_unit)

    Description: Converts a number to the interval type. num is a numeric-typed number. interval_unit is a string in the following format: 'DAY' | 'HOUR' | 'MINUTE' | 'SECOND'

    Example:

    openGauss=# SELECT numtodsinterval(100, 'HOUR');
     numtodsinterval 
    -----------------
     100:00:00
    (1 row)
    
    openGauss=# SET intervalstyle = a;
    SET
    openGauss=# SELECT numtodsinterval(100, 'HOUR');
            numtodsinterval
    -------------------------------
     +000000004 04:00:00.000000000
    (1 row)
    
  • pg_sleep(seconds)

    Description: Specifies the delay time of the server thread in unit of second.

    Return type: void

    Example:

    openGauss=# SELECT pg_sleep(10);
     pg_sleep 
    ----------
    
    (1 row)
    
  • statement_timestamp()

    Description: Specifies the current date and time.

    Return type: timestamp with time zone

    Example:

    openGauss=# SELECT statement_timestamp();
          statement_timestamp      
    -------------------------------
     2017-09-01 17:04:39.119267+08
    (1 row)
    
  • sysdate

    Description: Specifies the current date and time.

    Return type: timestamp

    Example:

    openGauss=# SELECT sysdate;
           sysdate       
    ---------------------
     2017-09-01 17:04:49
    (1 row)
    
  • timeofday()

    Description: Specifies the current date and time (like clock_timestamp, but returned as a text string)

    Return type: text

    Example:

    openGauss=# SELECT timeofday();
                  timeofday              
    -------------------------------------
     Fri Sep 01 17:05:01.167506 2017 CST
    (1 row)
    
  • transaction_timestamp()

    Description: Specifies the current date and time (equivalent to current_timestamp).

    Return type: timestamp with time zone

    Example:

    openGauss=# SELECT transaction_timestamp();
         transaction_timestamp     
    -------------------------------
     2017-09-01 17:05:13.534454+08
    (1 row)
    
  • add_months(d,n)

    Description: Returns the date date plus integer months.

    Return type: timestamp

    Example:

    openGauss=# SELECT add_months(to_date('2017-5-29', 'yyyy-mm-dd'), 11) FROM sys_dummy;
         add_months      
    ---------------------
     2018-04-29 00:00:00
    (1 row)
    
  • last_day(d)

    Description: Returns the date of the last day of the month that contains date.

    Return type: timestamp

    Example:

    openGauss=# select last_day(to_date('2017-01-01', 'YYYY-MM-DD')) AS cal_result;
         cal_result      
    ---------------------
     2017-01-31 00:00:00
    (1 row)
    
  • next_day(x,y)

    Description: Calculates the time of the next week y started from x.

    Return type: timestamp

    Example:

    openGauss=# select next_day(timestamp '2017-05-25 00:00:00','Sunday')AS cal_result;
         cal_result      
    ---------------------
     2017-05-28 00:00:00
    (1 row)
    
  • tinterval(abstime, abstime )

    Description: Creates a time interval with two pieces of absolute time.

    Return type: tinterval

    Example:

    openGauss=# call tinterval(abstime 'May 10, 1947 23:59:12', abstime 'Mon May  1 00:30:30 1995');
                          tinterval
    -----------------------------------------------------
     ["1947-05-10 23:59:12+09" "1995-05-01 00:30:30+08"]
    (1 row)
    
  • tintervalend(tinterval)

    Description: Returns the end time of tinterval.

    Return type: abstime

    Example:

    openGauss=# select tintervalend('["Sep 4, 1983 23:59:12" "Oct4, 1983 23:59:12"]');
          tintervalend
    ------------------------
     1983-10-04 23:59:12+08
    (1 row)
    
  • tintervalrel(tinterval)

    Description: Calculates and returns the relative time of tinterval.

    Return type: reltime

    Example:

    openGauss=# select tintervalrel('["Sep 4, 1983 23:59:12" "Oct4, 1983 23:59:12"]');
     tintervalrel
    --------------
     1 mon
    (1 row)
    

TIMESTAMPDIFF

  • TIMESTAMPDIFF(unit , timestamp_expr1, timestamp_expr2)

The timestampdiff function returns the result of timestamp_expr2timestamp_expr1 in the specified unit. timestamp_expr1 and timestamp_expr2 must be value expressions of timestamp, timestamptz, or** date** type. unit determines the unit of the difference between two dates.

NOTE: This function is valid only when openGauss is compatible with the MY type (that is, dbcompatibility = 'B').

  • year

    Calculates the number of years between two dates.

    openGauss=#  SELECT TIMESTAMPDIFF(YEAR, '2018-01-01', '2020-01-01');
     timestamp_diff
    ----------------
                  2
    (1 row)
    
  • quarter

    Calculates the number of quarters between two dates.

    openGauss=#  SELECT TIMESTAMPDIFF(QUARTER, '2018-01-01', '2020-01-01');
     timestamp_diff
    ----------------
                  8
    (1 row)
    
  • month

    Calculates the number of months between two dates.

    openGauss=#  SELECT TIMESTAMPDIFF(MONTH, '2018-01-01', '2020-01-01');
     timestamp_diff
    ----------------
                 24
    (1 row)
    
  • week

    Calculates the number of weeks between two dates.

    openGauss=#  SELECT TIMESTAMPDIFF(WEEK, '2018-01-01', '2020-01-01');
     timestamp_diff
    ----------------
                104
    (1 row)
    
  • day

    Calculates the number of days between two dates.

    openGauss=#  SELECT TIMESTAMPDIFF(DAY, '2018-01-01', '2020-01-01');
     timestamp_diff
    ----------------
                730
    (1 row)
    
  • hour

    Calculates the number of hours between two pieces of time.

    openGauss=#  SELECT TIMESTAMPDIFF(HOUR, '2020-01-01 10:10:10', '2020-01-01 11:11:11');
     timestamp_diff
    ----------------
                  1
    (1 row)
    
  • minute

    Calculates the number of minutes between two pieces of time.

    openGauss=#  SELECT TIMESTAMPDIFF(MINUTE, '2020-01-01 10:10:10', '2020-01-01 11:11:11');
     timestamp_diff
    ----------------
                 61
    (1 row)
    
  • second

    Calculates the number of seconds between two pieces of time.

    openGauss=#  SELECT TIMESTAMPDIFF(SECOND, '2020-01-01 10:10:10', '2020-01-01 11:11:11');
     timestamp_diff
    ----------------
               3661
    (1 row)
    
  • microseconds

    Calculates the number of seconds between two pieces of time, including fractional parts, multiplied by 1,000,000.

    openGauss=#  SELECT TIMESTAMPDIFF(MICROSECOND, '2020-01-01 10:10:10.000000', '2020-01-01 10:10:10.111111');
     timestamp_diff
    ----------------
             111111
    (1 row)
    
  • timestamp_expr (with a time zone)

    openGauss=# SELECT TIMESTAMPDIFF(HOUR,'2020-05-01 10:10:10-01','2020-05-01 10:10:10-03');
     timestamp_diff
    ----------------
                  2
    (1 row)
    

EXTRACT

  • EXTRACT(field_ _FROM source)

The extract function retrieves subcolumns such as year or hour from date or time values. source must be a value expression of timestamp, time, or interval type. (Expressions of the date type are cast to timestamp and can therefore be used as well.) field is an identifier or string that specifies the columns to be extracted from the source value. The extract function returns values of double precision type. The following are valid names of field:

  • century

    Specifies the number of centuries.

    The first century starts at 0001-01-01 00:00:00 AD. This definition applies to all Gregorian calendar countries. There is no century numbered 0. You go from the 1st century BC to the 1st century AD.

    Example:

    openGauss=# SELECT EXTRACT(CENTURY FROM TIMESTAMP '2000-12-16 12:21:13');
     date_part 
    -----------
            20
    (1 row)
    
  • day

    • Specifies the date (1–31) of the month for timestamp.

      openGauss=# SELECT EXTRACT(DAY FROM TIMESTAMP '2001-02-16 20:38:40');
       date_part 
      -----------
              16
      (1 row)
      
    • Specifies the number of days for interval.

      openGauss=# SELECT EXTRACT(DAY FROM INTERVAL '40 days 1 minute');
       date_part 
      -----------
              40
      (1 row)
      
  • decade

    Specifies the number of decades.

    openGauss=# SELECT EXTRACT(DECADE FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
           200
    (1 row)
    
  • dow

    Specifies the day of the week. The value range from 0 (indicating Sunday) to 6 (indicating Saturday).

    openGauss=# SELECT EXTRACT(DOW FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
             5
    (1 row)
    
  • doy

    Specifies the day of the year (1–365 or 1–366).

    openGauss=# SELECT EXTRACT(DOY FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
            47
    (1 row)
    
  • epoch

    • For timestamp with time zone, it specifies the number of seconds since 1970-01-01 00:00:00-00 UTC (can be negative).

      For date and timestamp, it specifies the number of seconds since 1970-01-01 00:00:00-00 (local time).

      For interval, it specifies the total number of seconds in the interval.

      openGauss=# SELECT EXTRACT(EPOCH FROM TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40.12-08');
        date_part   
      --------------
       982384720.12
      (1 row)
      
      openGauss=# SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
       date_part 
      -----------
          442800
      (1 row)
      
    • The following converts an epoch value back to a timestamp.

      openGauss=# SELECT TIMESTAMP WITH TIME ZONE 'epoch' + 982384720.12 * INTERVAL '1 second' AS RESULT;
                result          
      ---------------------------
       2001-02-17 12:38:40.12+08
      (1 row)
      
  • hour

    Specifies the hour column (0–23).

    openGauss=# SELECT EXTRACT(HOUR FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
            20
    (1 row)
    
  • isodow

    Specifies the day of the week (1–7).

    1 indicates Monday and 7 indicates Sunday.

    NOTE: This is identical to dow except for Sunday.

    openGauss=# SELECT EXTRACT(ISODOW FROM TIMESTAMP '2001-02-18 20:38:40');
     date_part 
    -----------
             7
    (1 row)
    
  • isoyear

    The ISO 8601 year that the date falls in (not applicable to intervals).

    Each ISO year begins with the Monday of the week containing January 4, so in early January or late December the ISO year may be different from the Gregorian year. See the week column for more information.

    openGauss=# SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-01');
     date_part 
    -----------
          2005
    (1 row)
    
    openGauss=# SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-02');
     date_part 
    -----------
          2006
    (1 row)
    
  • microseconds

    Specifies the second column, including fractional parts, multiplied by 1,000,000.

    openGauss=# SELECT EXTRACT(MICROSECONDS FROM TIME '17:12:28.5');
     date_part 
    -----------
      28500000
    (1 row)
    
  • millennium

    Specifies the number of millenniums.

    Years in the 1900s are in the second millennium. The third millennium started from January 1, 2001.

    openGauss=# SELECT EXTRACT(MILLENNIUM FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
             3
    (1 row)
    
  • milliseconds

    Specifies the second column, including fractional parts, multiplied by 1000. Note that this includes full seconds.

    openGauss=# SELECT EXTRACT(MILLISECONDS FROM TIME '17:12:28.5');
     date_part 
    -----------
         28500
    (1 row)
    
  • minute

    Specifies the minute column (0–59).

    openGauss=# SELECT EXTRACT(MINUTE FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
            38
    (1 row)
    
  • month

    For timestamp, it specifies the month in the year (1–12).

    openGauss=# SELECT EXTRACT(MONTH FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
             2
    (1 row)
    

    For interval, it specifies the number of months and modulo 12 (0–11).

    openGauss=# SELECT EXTRACT(MONTH FROM INTERVAL '2 years 13 months');
     date_part 
    -----------
             1
    (1 row)
    
  • quarter

    Specifies the quarter of the year (1–4) that the date is in.

    openGauss=# SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
             1
    (1 row)
    
  • second

    Specifies the second column, including fractional parts (0–59).

    openGauss=# SELECT EXTRACT(SECOND FROM TIME '17:12:28.5');
     date_part 
    -----------
          28.5
    (1 row)
    
  • timezone

    Time zone offset from UTC, measured in seconds. Positive values correspond to time zones east of UTC, and negative values correspond to zones west of UTC.

  • timezone_hour

    Hour part of the time zone offset.

  • timezone_minute

    Minute part of the time zone offset.

  • week

    Number of the week of the year that the day is in. By definition (ISO 8601), the first week of a year contains January 4 of that year. (The ISO-8601 week starts on Monday.) In other words, the first Thursday of a year is in week 1 of that year.

    Because of this, it is possible for early January dates to be part of the 52nd or 53rd week of the previous year, and late December dates to be part of the 1st week of the next year. For example, 2005-01-01 is part of the 53rd week of year 2004, 2006-01-01 is part of the 52nd week of year 2005, and 2012-12-31 is part of the 1st week of year 2013. You are advised to use the columns isoyear and week together to ensure consistency.

    openGauss=# SELECT EXTRACT(WEEK FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
             7
    (1 row)
    
  • year

    Specifies the year column.

    openGauss=# SELECT EXTRACT(YEAR FROM TIMESTAMP '2001-02-16 20:38:40');
     date_part 
    -----------
          2001
    (1 row)
    

date_part

The date_part function is modeled on the traditional Ingres equivalent to the SQL-standard function extract.

  • date_part(**'field', **source)

Note that here the field parameter needs to be a string value, not a name. The valid field names for date_part are the same as those for extract. For details, see EXTRACT.

Example:

openGauss=# SELECT date_part('day', TIMESTAMP '2001-02-16 20:38:40');
 date_part 
-----------
        16
(1 row)
openGauss=# SELECT date_part('hour', INTERVAL '4 hours 3 minutes');
 date_part 
-----------
         4
(1 row)

Table 2 specifies the schema for formatting date and time values.

Table 2 Schema for formatting date and time values

Category

Pattern

Description

Hour

HH

Number of hours in one day (01–12)

HH12

Number of hours in one day (01–12)

HH24

Number of hours in one day (00–23)

Minute

MI

Minute (00–59)

Second

SS

Second (00–59)

FF

Microsecond (000000–999999)

SSSSS

Second after midnight (0–86399)

Morning and afternoon

AM or A.M.

Morning identifier

PM or P.M.

Afternoon identifier

Year

Y,YYY

Year with commas (with four digits or more)

SYYYY

Year with four digits BC

YYYY

Year (with four digits or more)

YYY

Last three digits of a year

YY

Last two digits of a year

Y

Last one digit of a year

IYYY

ISO year (with four digits or more)

IYY

Last three digits of an ISO year

IY

Last two digits of an ISO year

I

Last one digit of an ISO year

RR

Last two digits of a year (A year of the 20th century can be stored in the 21st century.)

RRRR

Capable of receiving a year with four digits or two digits. If there are 2 digits, the value is the same as the returned value of RR. If there are 4 digits, the value is the same as YYYY.

  • BC or B.C.
  • AD or A.D.

Era indicator Before Christ (BC) and After Christ (AD)

Month

MONTH

Full spelling of a month in uppercase (9 characters are filled in if the value is empty.)

MON

Month in abbreviated format in uppercase (with three characters)

MM

Month (01–12)

RM

Month in Roman numerals (I–XII; I=JAN) and uppercase

Day

DAY

Full spelling of a date in uppercase (9 characters are filled in if the value is empty.)

DY

Day in abbreviated format in uppercase (with three characters)

DDD

Day in a year (001–366)

DD

Day in a month (01–31)

D

Day in a week (1–7)

Week

W

Week in a month (1–5) (The first week starts from the first day of the month.)

WW

Week in a year (1–53) (The first week starts from the first day of the year.)

IW

Week in an ISO year (The first Thursday is in the first week.)

Century

CC

Century (with two digits) (The 21st century starts from 2001-01-01.)

Julian date

J

Julian date (starting from January 1 of 4712 BC)

Quarter

Q

Quarter

NOTE: In the table, the rules for RR to calculate years are as follows:

  • If the range of the input two-digit year is between 00 and 49: If the last two digits of the current year are between 00 and 49, the first two digits of the returned year are the same as the first two digits of the current year. If the last two digits of the current year are between 50 and 99, the first two digits of the returned year are equal to the first two digits of the current year plus 1.
  • If the range of the input two-digit year is between 50 and 99: If the last two digits of the current year are between 00 and 49, the first two digits of the returned year are equal to the first two digits of the current year minus 1. If the last two digits of the current year are between 50 and 99, the first two digits of the returned year are the same as the first two digits of the current year.
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