This is the multi-page printable view of this section. Click here to print.

Return to the regular view of this page.

Date/time functions

Date and time functions perform conversion, extraction, or manipulation operations on date and time data types and can return date and time information.

1: ADD_MONTHS
2: AGE_IN_MONTHS
3: AGE_IN_YEARS
4: CLOCK_TIMESTAMP
5: CURRENT_DATE
6: CURRENT_TIME
7: CURRENT_TIMESTAMP
8: DATE
9: DATE_PART
10: DATE_TRUNC
11: DATEDIFF
12: DAY
13: DAYOFMONTH
14: DAYOFWEEK
15: DAYOFWEEK_ISO
16: DAYOFYEAR
17: DAYS
18: EXTRACT
19: GETDATE
20: GETUTCDATE
21: HOUR
22: ISFINITE
23: JULIAN_DAY
24: LAST_DAY
25: LOCALTIME
26: LOCALTIMESTAMP
27: MICROSECOND
28: MIDNIGHT_SECONDS
29: MINUTE
30: MONTH
31: MONTHS_BETWEEN
32: NEW_TIME
33: NEXT_DAY
34: NOW [date/time]
35: OVERLAPS
36: QUARTER
37: ROUND
38: SECOND
39: STATEMENT_TIMESTAMP
40: SYSDATE
41: TIME_SLICE
42: TIMEOFDAY
43: TIMESTAMP_ROUND
44: TIMESTAMP_TRUNC
45: TIMESTAMPADD
46: TIMESTAMPDIFF
47: TRANSACTION_TIMESTAMP
48: TRUNC
49: WEEK
50: WEEK_ISO
51: YEAR
52: YEAR_ISO

Date and time functions perform conversion, extraction, or manipulation operations on date and time data types and can return date and time information.

Usage

Functions that take TIME or TIMESTAMP inputs come in two variants:

TIME WITH TIME ZONE or TIMESTAMP WITH TIME ZONE
TIME WITHOUT TIME ZONE or TIMESTAMP WITHOUT TIME ZONE

For brevity, these variants are not shown separately.

The + and * operators come in commutative pairs; for example, both DATE + INTEGER and INTEGER + DATE. We show only one of each such pair.

Daylight savings time considerations

When adding an INTERVAL value to (or subtracting an INTERVAL value from) a TIMESTAMP WITH TIME ZONE value, the days component advances (or decrements) the date of the TIMESTAMP WITH TIME ZONE by the indicated number of days. Across daylight saving time changes (with the session time zone set to a time zone that recognizes DST), this means INTERVAL '1 day' does not necessarily equal INTERVAL '24 hours'.

For example, with the session time zone set to CST7CDT:

TIMESTAMP WITH TIME ZONE '2014-04-02 12:00-07' + INTERVAL '1 day'

produces

TIMESTAMP WITH TIME ZONE '2014-04-03 12:00-06'

Adding INTERVAL '24 hours' to the same initial TIMESTAMP WITH TIME ZONE produces

TIMESTAMP WITH TIME ZONE '2014-04-03 13:00-06',

This result occurs because there is a change in daylight saving time at 2014-04-03 02:00 in time zone CST7CDT.

Date/time functions in transactions

Certain date/time functions such as CURRENT_TIMESTAMP and NOW return the start time of the current transaction; for the duration of that transaction, they return the same value. Other date/time functions such as TIMEOFDAY always return the current time.

1 - ADD_MONTHS

Adds the specified number of months to a date and returns the sum as a DATE.

Adds the specified number of months to a date and returns the sum as a DATE. In general, ADD_MONTHS returns a date with the same day component as the start date. For example:

=> SELECT ADD_MONTHS ('2015-09-15'::date, -2) "2 Months Ago";
 2 Months Ago
--------------
 2015-07-15
(1 row)

Two exceptions apply:

If the start date's day component is greater than the last day of the result month, ADD_MONTHS returns the last day of the result month. For example:
```
=> SELECT ADD_MONTHS ('31-Jan-2016'::TIMESTAMP, 1) "Leap Month";
 Leap Month
------------
 2016-02-29
(1 row)
```
If the start date's day component is the last day of that month, and the result month has more days than the start date month, ADD_MONTHS returns the last day of the result month. For example:
```
=> SELECT ADD_MONTHS ('2015-09-30'::date,-1) "1 Month Ago";
 1 Month Ago
-------------
 2015-08-31
(1 row)
```

Behavior type

Immutable if the start-date argument is a TIMESTAMP or DATE
Stable if the start-date argument is a TIMESTAMPTZ

Syntax

ADD_MONTHS ( start-date, num-months );

Parameters

start-date

The date to process, an expression that evaluates to one of the following data types:

DATE
TIMESTAMP
TIMESTAMPTZ

num-months

An integer expression that specifies the number of months to add to or subtract from start-date.

Examples

Add one month to the current date:

=> SELECT CURRENT_DATE Today;
   Today
------------
 2016-05-05
(1 row)

VMart=> SELECT ADD_MONTHS(CURRENT_TIMESTAMP,1);
 ADD_MONTHS
------------
 2016-06-05
(1 row)

Subtract four months from the current date:

=> SELECT ADD_MONTHS(CURRENT_TIMESTAMP, -4);
 ADD_MONTHS
------------
 2016-01-05
(1 row)

Add one month to January 31 2016:

=> SELECT ADD_MONTHS('31-Jan-2016'::TIMESTAMP, 1) "Leap Month";
 Leap Month
------------
 2016-02-29
(1 row)

The following example sets the timezone to EST; it then adds 24 months to a TIMESTAMPTZ that specifies a PST time zone, so ADD_MONTHS takes into account the time change:

=> SET TIME ZONE 'America/New_York';
SET
VMart=> SELECT ADD_MONTHS('2008-02-29 23:30 PST'::TIMESTAMPTZ, 24);
 ADD_MONTHS
------------
 2010-03-01
(1 row)

2 - AGE_IN_MONTHS

Returns the difference in months between two dates, expressed as an integer.

Behavior type

Immutable if both date arguments are of data type TIMESTAMP
Stable if either date is a TIMESTAMPTZ or only one argument is supplied

Syntax

AGE_IN_MONTHS ( [ date1,] date2 )

Parameters

date1 date2

Specify the boundaries of the period to measure. If you supply only one argument, Vertica sets date2 to the current date. Both parameters must evaluate to one of the following data types:

DATE
TIMESTAMP
TIMESTAMPTZ

If date1 < date2, AGE_IN_MONTHS returns a negative value.

Examples

Get the age in months of someone born March 2 1972, as of June 21 1990:

=> SELECT AGE_IN_MONTHS('1990-06-21'::TIMESTAMP, '1972-03-02'::TIMESTAMP);
  AGE_IN_MONTHS
---------------
           219
(1 row)

If the first date is less than the second date, AGE_IN_MONTHS returns a negative value

=> SELECT AGE_IN_MONTHS('1972-03-02'::TIMESTAMP, '1990-06-21'::TIMESTAMP);
AGE_IN_MONTHS
---------------
-220
(1 row)

Get the age in months of someone who was born November 21 1939, as of today:

=> SELECT AGE_IN_MONTHS ('1939-11-21'::DATE);
 AGE_IN_MONTHS
---------------
           930
(1 row)

3 - AGE_IN_YEARS

Returns the difference in years between two dates, expressed as an integer.

Behavior type

Immutable if both date arguments are of data type TIMESTAMP
Stable if either date is a TIMESTAMPTZ or only one argument is supplied

Syntax

AGE_IN_YEARS( [ date1,] date2 )

Parameters

date1 date2

Specify the boundaries of the period to measure. If you supply only one argument, Vertica sets date1 to the current date. Both parameters must evaluate to one of the following data types:

DATE
TIMESTAMP
TIMESTAMPTZ

If date1 < date2, AGE_IN_YEARS returns a negative value.

Examples

Get the age of someone born March 2 1972, as of June 21 1990:

=> SELECT AGE_IN_YEARS('1990-06-21'::TIMESTAMP, '1972-03-02'::TIMESTAMP);
 AGE_IN_YEARS
--------------
           18
(1 row)

If the first date is earlier than the second date, AGE_IN_YEARS returns a negative number:

=> SELECT AGE_IN_YEARS('1972-03-02'::TIMESTAMP, '1990-06-21'::TIMESTAMP);
AGE_IN_YEARS
--------------
          -19
(1 row)

Get the age of someone who was born November 21 1939, as of today:

=> SELECT AGE_IN_YEARS('1939-11-21'::DATE);
 AGE_IN_YEARS
--------------
           77
(1 row)

4 - CLOCK_TIMESTAMP

Returns a value of type TIMESTAMP WITH TIMEZONE that represents the current system-clock time.

CLOCK_TIMESTAMP uses the date and time supplied by the operating system on the server to which you are connected, which should be the same across all servers. The value changes each time you call it.

Behavior type

Volatile

Syntax

CLOCK_TIMESTAMP()

Examples

The following command returns the current time on your system:

SELECT CLOCK_TIMESTAMP() "Current Time";
         Current Time
------------------------------
 2010-09-23 11:41:23.33772-04
(1 row)

Each time you call the function, you get a different result. The difference in this example is in microseconds:

SELECT CLOCK_TIMESTAMP() "Time 1", CLOCK_TIMESTAMP() "Time 2";
            Time 1             |            Time 2
-------------------------------+-------------------------------
 2010-09-23 11:41:55.369201-04 | 2010-09-23 11:41:55.369202-04
(1 row)

5 - CURRENT_DATE

Returns the date (date-type value) on which the current transaction started.

Behavior type

Stable

Syntax

CURRENT_DATE()

Note

You can call this function without parentheses.

Examples

SELECT CURRENT_DATE;
  ?column?
------------
 2010-09-23
(1 row)

6 - CURRENT_TIME

Returns a value of type TIME WITH TIMEZONE that represents the start of the current transaction.

Returns a value of type TIME WITH TIMEZONE that represents the start of the current transaction.

The return value does not change during the transaction. Thus, multiple calls to CURRENT_TIME within the same transaction return the same timestamp.

Behavior type

Stable

Syntax

CURRENT_TIME  [ ( precision ) ]

Note

If you specify a column label without precision, you must also omit parentheses.

Parameters

precision: An integer value between 0-6, specifies to round the seconds fraction field result to the specified number of digits.

Examples


=> SELECT CURRENT_TIME(1) AS Time;
     Time
---------------
 06:51:45.2-07
(1 row)
=> SELECT CURRENT_TIME(5) AS Time;
       Time
-------------------
 06:51:45.18435-07
(1 row)

7 - CURRENT_TIMESTAMP

Returns a value of type TIME WITH TIMEZONE that represents the start of the current transaction.

Returns a value of type TIME WITH TIMEZONE that represents the start of the current transaction.

The return value does not change during the transaction. Thus, multiple calls to CURRENT_TIMESTAMP within the same transaction return the same timestamp.

Behavior type

Stable

Syntax

CURRENT_TIMESTAMP ( precision )

Parameters

precision: An integer value between 0-6, specifies to round the seconds fraction field result to the specified number of digits.

Examples


=> SELECT CURRENT_TIMESTAMP(1) AS time;
           time
--------------------------
 2017-03-27 06:50:49.7-07
(1 row)
=> SELECT CURRENT_TIMESTAMP(5) AS time;
             time
------------------------------
 2017-03-27 06:50:49.69967-07
(1 row)

8 - DATE

Converts the input value to a DATE data type.

Converts the input value to a DATE data type.

Behavior type

Immutable if the input value is a TIMESTAMP, DATE, VARCHAR, or integer
Stable if the input value is a TIMESTAMPTZ

Syntax

DATE ( value )

Parameters

value

The value to convert, one of the following:

TIMESTAMP, TIMESTAMPTZ, VARCHAR, or another DATE.
Integer: Vertica treats the integer as the number of days since 01/01/0001 and returns the date.

Examples

=> SELECT DATE (1);
    DATE
------------
 0001-01-01
(1 row)

=> SELECT DATE (734260);
    DATE
------------
 2011-05-03
(1 row)

=> SELECT DATE('TODAY');
    DATE
------------
 2016-12-07
(1 row)

9 - DATE_PART

Extracts a sub-field such as year or hour from a date/time expression, equivalent to the the SQL-standard function EXTRACT.

Extracts a sub-field such as year or hour from a date/time expression, equivalent to the the SQL-standard function EXTRACT.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or INTERVAL
Stable if the specified date is a TIMESTAMPTZ

Syntax

DATE_PART ( 'field', date )

Parameters

field

A constant value that specifies the sub-field to extract from date (see Field Values below).

date

The date to process, an expression that evaluates to one of the following data types:

DATE (cast to TIMESTAMP)
TIMESTAMP/TIMESTAMPTZ
INTERVAL

Field values

CENTURY

The century number.

The first century starts at 0001-01-01 00:00:00 AD. This definition applies to all Gregorian calendar countries. There is no century number 0, you go from –1 to 1.

DAY

The day (of the month) field (1–31).

DECADE

The year field divided by 10.

DOQ

The day within the current quarter. DOQ recognizes leap year days.

DOW

Zero-based day of the week, where Sunday=0.

Note

EXTRACT's day of week numbering differs from the function TO_CHAR .

DOY

The day of the year (1–365/366)

EPOCH

Specifies to return one of the following:

For DATE and TIMESTAMP values: the number of seconds before or since 1970-01-01 00:00:00-00 (if before, a negative number).
For INTERVAL values, the total number of seconds in the interval.

HOUR

The hour field (0–23).

ISODOW

The ISO day of the week, an integer between 1 and 7 where Monday is 1.

ISOWEEK

The ISO week of the year, an integer between 1 and 53.

ISOYEAR

The ISO year.

MICROSECONDS

The seconds field, including fractional parts, multiplied by 1,000,000. This includes full seconds.

MILLENNIUM

The millennium number, where the first millennium is 1 and each millenium starts on 01-01-y001. For example, millennium 2 starts on 01-01-1001.

MILLISECONDS

The seconds field, including fractional parts, multiplied by 1000. This includes full seconds.

MINUTE

The minutes field (0 - 59).

MONTH

For TIMESTAMP values, the number of the month within the year (1 - 12) ; for interval values the number of months, modulo 12 (0 - 11).

QUARTER

The calendar quarter of the specified date as an integer, where the January-March quarter is 1, valid only for TIMESTAMP values.

SECOND

The seconds field, including fractional parts, 0–59, or 0-60 if the operating system implements leap seconds.

TIME ZONE

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

TIMEZONE_HOUR

The hour component of the time zone offset.

TIMEZONE_MINUTE

The minute component of the time zone offset.

WEEK

The number of the week of the calendar year that the day is in.

YEAR

The year field. There is no 0 AD, so subtract BC years from AD years accordingly.

Notes

According to the ISO-8601 standard, the week starts on Monday, and the first week of a year contains January 4. Thus, an early January date can sometimes be in the week 52 or 53 of the previous calendar year. For example:

=> SELECT YEAR_ISO('01-01-2016'::DATE), WEEK_ISO('01-01-2016'), DAYOFWEEK_ISO('01-01-2016');
 YEAR_ISO | WEEK_ISO | DAYOFWEEK_ISO
----------+----------+---------------
     2015 |       53 |             5
(1 row)

Examples

Extract the day value:

SELECT DATE_PART('DAY', TIMESTAMP '2009-02-24 20:38:40') "Day";
  Day
-----
  24
(1 row)

Extract the month value:

SELECT DATE_PART('MONTH', '2009-02-24 20:38:40'::TIMESTAMP) "Month";
  Month
-------
     2
(1 row)

Extract the year value:

SELECT DATE_PART('YEAR', '2009-02-24 20:38:40'::TIMESTAMP) "Year";
  Year
------
 2009
(1 row)

Extract the hours:

SELECT DATE_PART('HOUR', '2009-02-24 20:38:40'::TIMESTAMP) "Hour";
  Hour
------
   20
(1 row)

Extract the minutes:

SELECT DATE_PART('MINUTES', '2009-02-24 20:38:40'::TIMESTAMP) "Minutes";
  Minutes
---------
      38
(1 row)

Extract the day of quarter (DOQ):

SELECT DATE_PART('DOQ', '2009-02-24 20:38:40'::TIMESTAMP) "DOQ";
 DOQ
-----
  55
(1 row)

10 - DATE_TRUNC

Truncates date and time values to the specified precision.

Truncates date and time values to the specified precision. The return value is the same data type as the input value. All fields that are less than the specified precision are set to 0, or to 1 for day and month.

Behavior type

Stable

Syntax

DATE_TRUNC( precision, trunc-target )

Parameters

precision: A string constant that specifies precision for the truncated value. See Precision Field Values below. The precision must be valid for the trunc-target date or time.
trunc-target: Valid date/time expression.

Precision field values

MILLENNIUM

The millennium number.

CENTURY

The century number.

The first century starts at 0001-01-01 00:00:00 AD. This definition applies to all Gregorian calendar countries.

DECADE

The year field divided by 10.

YEAR

The year field. Keep in mind there is no 0 AD, so subtract BC years from AD years with care.

QUARTER

The calendar quarter of the specified date as an integer, where the January-March quarter is 1.

MONTH

For timestamp values, the number of the month within the year (1–12) ; for interval values the number of months, modulo 12 (0–11).

WEEK

The number of the week of the year that the day is in.

=> SELECT YEAR_ISO('01-01-2016'::DATE), WEEK_ISO('01-01-2016'), DAYOFWEEK_ISO('01-01-2016');
 YEAR_ISO | WEEK_ISO | DAYOFWEEK_ISO
----------+----------+---------------
     2015 |       53 |             5
(1 row)

DAY

The day (of the month) field (1–31).

HOUR

The hour field (0–23).

MINUTE

The minutes field (0–59).

SECOND

The seconds field, including fractional parts (0–59) (60 if leap seconds are implemented by the operating system).

MILLISECONDS

The seconds field, including fractional parts, multiplied by 1000. Note that this includes full seconds.

MICROSECONDS

The seconds field, including fractional parts, multiplied by 1,000,000. This includes full seconds.

Examples

The following example sets the field value as hour and returns the hour, truncating the minutes and seconds:

=> SELECT DATE_TRUNC('HOUR', TIMESTAMP '2012-02-24 13:38:40') AS HOUR;
        HOUR
---------------------
 2012-02-24 13:00:00
(1 row)

The following example returns the year from the input timestamptz '2012-02-24 13:38:40'. The function also defaults the month and day to January 1, truncates the hour:minute:second of the timestamp, and appends the time zone (-05):

=> SELECT DATE_TRUNC('YEAR', TIMESTAMPTZ '2012-02-24 13:38:40') AS YEAR;
          YEAR
------------------------
 2012-01-01 00:00:00-05
(1 row)

The following example returns the year and month and defaults day of month to 1, truncating the rest of the string:

=> SELECT DATE_TRUNC('MONTH', TIMESTAMP '2012-02-24 13:38:40') AS MONTH;
        MONTH
---------------------
 2012-02-01 00:00:00
(1 row)

11 - DATEDIFF

Returns the time span between two dates, in the intervals specified.

Returns the time span between two dates, in the intervals specified. DATEDIFF excludes the start date in its calculation.

Behavior type

Immutable if start and end dates are TIMESTAMP , DATE, TIME, or INTERVAL
Stable if start and end dates are TIMESTAMPTZ

Syntax

DATEDIFF ( datepart, start, end );

Parameters

datepart

Specifies the type of date or time intervals that DATEDIFF returns. If datepart is an expression, it must be enclosed in parentheses:

DATEDIFF((expression), start, end);

datepart must evaluate to one of the following string literals, either quoted or unquoted:

year | yy | yyyy
quarter | qq | q
month | mm | m
day | dayofyear | dd | d | dy | y
week | wk | ww
hour | hh
minute | mi | n
second | ss | s
millisecond | ms
microsecond | mcs | us

start, end

Specify the start and end dates, where start and end evaluate to one of the following data types:

If end < start, DATEDIFF returns a negative value.

Note

TIME and INTERVAL data types are invalid for start and end dates if datepart is set to year, quarter, or month.

Compatible start and end date data types

The following table shows which data types can be matched as start and end dates:

	`DATE`	`TIMESTAMP`	`TIMESTAMPTZ`	`TIME`	`INTERVAL`
`DATE`	•	•	•
`TIMESTAMP`	•	•	•
`TIMESTAMPTZ`	•	•	•
`TIME`				•
`INTERVAL`					•

For example, if you set the start date to an INTERVAL data type, the end date must also be an INTERVAL, otherwise Vertica returns an error:

 SELECT DATEDIFF(day, INTERVAL '26 days', INTERVAL '1 month ');
 datediff
----------
        4
(1 row)

Date part intervals

DATEDIFF uses the datepart argument to calculate the number of intervals between two dates, rather than the actual amount of time between them. DATEDIFF uses the following cutoff points to calculate those intervals:

year: January 1
quarter: January 1, April 1, July 1, October 1
month: the first day of the month
week: Sunday at midnight (24:00)

For example, if datepart is set to year, DATEDIFF uses January 01 to calculate the number of years between two dates. The following DATEDIFF statement sets datepart to year, and specifies a time span 01/01/2005 - 06/15/2008:

SELECT DATEDIFF(year, '01-01-2005'::date, '12-31-2008'::date);
 datediff
----------
        3
(1 row)

DATEDIFF always excludes the start date when it calculates intervals—in this case, 01/01//2005. DATEDIFF considers only calendar year starts in its calculation, so in this case it only counts years 2006, 2007, and 2008. The function returns 3, although the actual time span is nearly four years.

If you change the start and end dates to 12/31/2004 and 01/01/2009, respectively, DATEDIFF also counts years 2005 and 2009. This time, it returns 5, although the actual time span is just over four years:

=> SELECT DATEDIFF(year, '12-31-2004'::date, '01-01-2009'::date);
 datediff
----------
        5
(1 row)

Similarly, DATEDIFF uses month start dates when it calculates the number of months between two dates. Thus, given the following statement, DATEDIFF counts months February through September and returns 8:

=> SELECT DATEDIFF(month, '01-31-2005'::date, '09-30-2005'::date);
 datediff
----------
        8
(1 row)

12 - DAY

Returns as an integer the day of the month from the input value.

Behavior type

Immutable if the input value is a TIMESTAMP, DATE, VARCHAR, or INTEGER
Stable if the specified date is a TIMESTAMPTZ

Syntax

DAY ( value )

Parameters

value: The value to convert, one of the following: TIMESTAMP, TIMESTAMPTZ, INTERVAL, VARCHAR, or INTEGER.

Examples

=> SELECT DAY (6);
 DAY
-----
   6
(1 row)

=> SELECT DAY(TIMESTAMP 'sep 22, 2011 12:34');
 DAY
-----
  22
(1 row)

=> SELECT DAY('sep 22, 2011 12:34');
 DAY
-----
  22
(1 row)

=> SELECT DAY(INTERVAL '35 12:34');
 DAY
-----
  35
(1 row)

13 - DAYOFMONTH

Returns the day of the month as an integer.

Behavior type

Immutable if thetarget date is a TIMESTAMP, DATE, or VARCHAR
Stable if the target date is aTIMESTAMPTZ

Syntax

DAYOFMONTH ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT DAYOFMONTH (TIMESTAMP 'sep 22, 2011 12:34');
 DAYOFMONTH
------------
         22
(1 row)

14 - DAYOFWEEK

Returns the day of the week as an integer, where Sunday is day 1.

Behavior type

Immutable if thetarget date is a TIMESTAMP, DATE, or VARCHAR
Stable if the target date is aTIMESTAMPTZ

Syntax

DAYOFWEEK ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT DAYOFWEEK (TIMESTAMP 'sep 17, 2011 12:34');
 DAYOFWEEK
-----------
         7
(1 row)

15 - DAYOFWEEK_ISO

Returns the ISO 8061 day of the week as an integer, where Monday is day 1.

Behavior type

Immutable if thetarget date is a TIMESTAMP, DATE, or VARCHAR
Stable if the target date is aTIMESTAMPTZ

Syntax

DAYOFWEEK_ISO ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT DAYOFWEEK_ISO(TIMESTAMP 'Sep 22, 2011 12:34');
 DAYOFWEEK_ISO
---------------
             4
(1 row)

The following example shows how to combine the DAYOFWEEK_ISO, WEEK_ISO, and YEAR_ISO functions to find the ISO day of the week, week, and year:

=> SELECT DAYOFWEEK_ISO('Jan 1, 2000'), WEEK_ISO('Jan 1, 2000'),YEAR_ISO('Jan1,2000');
 DAYOFWEEK_ISO | WEEK_ISO | YEAR_ISO
---------------+----------+----------
             6 |       52 |     1999
(1 row)

16 - DAYOFYEAR

Returns the day of the year as an integer, where January 1 is day 1.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

DAYOFYEAR ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT DAYOFYEAR (TIMESTAMP 'SEPT 22,2011 12:34');
 DAYOFYEAR
-----------
       265
(1 row)

17 - DAYS

Returns the integer value of the specified date, where 1 AD is 1.

Returns the integer value of the specified date, where 1 AD is 1. If the date precedes 1 AD, DAYS returns a negative integer.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

DAYS ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT DAYS (DATE '2011-01-22');
  DAYS
--------
 734159
(1 row)

=> SELECT DAYS (DATE 'March 15, 0044 BC');
  DAYS
--------
 -15997
(1 row)

18 - EXTRACT

Retrieves sub-fields such as year or hour from date/time values and returns values of type NUMERIC.

Retrieves sub-fields such as year or hour from date/time values and returns values of type NUMERIC. EXTRACT is intended for computational processing, rather than for formatting date/time values for display.

Behavior type

Immutable if the specified date is a TIMESTAMP, DATE, or INTERVAL
Stable if the specified date is aTIMESTAMPTZ

Syntax

EXTRACT ( field FROM date )

Parameters

field

A constant value that specifies the sub-field to extract from date (see Field Values below).

date

The date to process, an expression that evaluates to one of the following data types:

DATE (cast to TIMESTAMP)
TIMESTAMP/TIMESTAMPTZ
INTERVAL

Field values

CENTURY

The century number.

The first century starts at 0001-01-01 00:00:00 AD. This definition applies to all Gregorian calendar countries. There is no century number 0, you go from –1 to 1.

DAY

The day (of the month) field (1–31).

DECADE

The year field divided by 10.

DOQ

The day within the current quarter. DOQ recognizes leap year days.

DOW

Zero-based day of the week, where Sunday=0.

Note

EXTRACT's day of week numbering differs from the function TO_CHAR .

DOY

The day of the year (1–365/366)

EPOCH

Specifies to return one of the following:

For DATE and TIMESTAMP values: the number of seconds before or since 1970-01-01 00:00:00-00 (if before, a negative number).
For INTERVAL values, the total number of seconds in the interval.

HOUR

The hour field (0–23).

ISODOW

The ISO day of the week, an integer between 1 and 7 where Monday is 1.

ISOWEEK

The ISO week of the year, an integer between 1 and 53.

ISOYEAR

The ISO year.

MICROSECONDS

The seconds field, including fractional parts, multiplied by 1,000,000. This includes full seconds.

MILLENNIUM

The millennium number, where the first millennium is 1 and each millenium starts on 01-01-y001. For example, millennium 2 starts on 01-01-1001.

MILLISECONDS

The seconds field, including fractional parts, multiplied by 1000. This includes full seconds.

MINUTE

The minutes field (0 - 59).

MONTH

For TIMESTAMP values, the number of the month within the year (1 - 12) ; for interval values the number of months, modulo 12 (0 - 11).

QUARTER

The calendar quarter of the specified date as an integer, where the January-March quarter is 1, valid only for TIMESTAMP values.

SECOND

The seconds field, including fractional parts, 0–59, or 0-60 if the operating system implements leap seconds.

TIME ZONE

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

TIMEZONE_HOUR

The hour component of the time zone offset.

TIMEZONE_MINUTE

The minute component of the time zone offset.

WEEK

The number of the week of the calendar year that the day is in.

YEAR

The year field. There is no 0 AD, so subtract BC years from AD years accordingly.

Examples

Extract the day of the week and day in quarter from the current TIMESTAMP:

=> SELECT CURRENT_TIMESTAMP AS NOW;
              NOW
-------------------------------
 2016-05-03 11:36:08.829004-04
(1 row)
=> SELECT EXTRACT (DAY FROM CURRENT_TIMESTAMP);
 date_part
-----------
         3
(1 row)
=> SELECT EXTRACT (DOQ FROM CURRENT_TIMESTAMP);
 date_part
-----------
        33
(1 row)

Extract the timezone hour from the current time:

=> SELECT CURRENT_TIMESTAMP;
           ?column?
-------------------------------
 2016-05-03 11:36:08.829004-04
(1 row)

=>  SELECT EXTRACT(TIMEZONE_HOUR FROM CURRENT_TIMESTAMP);
 date_part
-----------
        -4
(1 row)

Extract the number of seconds since 01-01-1970 00:00:

=> SELECT EXTRACT(EPOCH FROM '2001-02-16 20:38:40-08'::TIMESTAMPTZ);
    date_part
------------------
 982384720.000000
(1 row)

Extract the number of seconds between 01-01-1970 00:00 and 5 days 3 hours before:

=> SELECT EXTRACT(EPOCH FROM -'5 days 3 hours'::INTERVAL);
   date_part
----------------
 -442800.000000
(1 row)

Convert the results from the last example to a TIMESTAMP:

=> SELECT 'EPOCH'::TIMESTAMPTZ -442800  * '1 second'::INTERVAL;
        ?column?
------------------------
 1969-12-26 16:00:00-05
(1 row)

19 - GETDATE

Returns the current statement's start date and time as a TIMESTAMP value.

Returns the current statement's start date and time as a TIMESTAMP value. This function is identical to SYSDATE.

GETDATE uses the date and time supplied by the operating system on the server to which you are connected, which is the same across all servers. Internally, GETDATE converts STATEMENT_TIMESTAMP from TIMESTAMPTZ to TIMESTAMP.

Behavior type

Stable

Syntax

GETDATE()

Examples

=> SELECT GETDATE();
          GETDATE
----------------------------
 2011-03-07 13:21:29.497742
(1 row)

20 - GETUTCDATE

Returns the current statement's start date and time as a TIMESTAMP value.

Returns the current statement's start date and time as a TIMESTAMP value.

GETUTCDATE uses the date and time supplied by the operating system on the server to which you are connected, which is the same across all servers. Internally, GETUTCDATE converts STATEMENT_TIMESTAMP at TIME ZONE 'UTC'.

Behavior type

Stable

Syntax

GETUTCDATE()

Examples

=> SELECT GETUTCDATE();
         GETUTCDATE
----------------------------
 2011-03-07 20:20:26.193052
(1 row)

21 - HOUR

Returns the hour portion of the specified date as an integer, where 0 is 00:00 to 00:59.

Behavior type

Immutable if thespecified date is a TIMESTAMP
Stable if the specified date is aTIMESTAMPTZ

Syntax

HOUR( date )

Parameters

date

The date to process, one of the following data types:

INTERVAL

Examples

=> SELECT HOUR (TIMESTAMP 'sep 22, 2011 12:34');
 HOUR
------
   12
(1 row)
=> SELECT HOUR (INTERVAL '35 12:34');
 HOUR
------
   12
(1 row)
=> SELECT HOUR ('12:34');
 HOUR
------
   12
(1 row)

22 - ISFINITE

Tests for the special TIMESTAMP constant INFINITY and returns a value of type BOOLEAN.

Tests for the special TIMESTAMP constant INFINITY and returns a value of type BOOLEAN.

Behavior type

Immutable

Syntax

ISFINITE ( timestamp )

Parameters

timestamp: Expression of type TIMESTAMP

Examples

SELECT ISFINITE(TIMESTAMP '2009-02-16 21:28:30');
 ISFINITE
----------
 t
(1 row)
SELECT ISFINITE(TIMESTAMP 'INFINITY');
 ISFINITE
----------
 f
(1 row)

23 - JULIAN_DAY

Returns the integer value of the specified day according to the Julian calendar, where day 1 is the first day of the Julian period, January 1, 4713 BC (on the Gregorian calendar, November 24, 4714 BC).

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

JULIAN_DAY ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT JULIAN_DAY (DATE 'MARCH 15, 0044 BC');
 JULIAN_DAY
------------
    1705428
(1 row)

=> SELECT JULIAN_DAY (DATE '2001-01-01');
 JULIAN_DAY
------------
    2451911
(1 row)

24 - LAST_DAY

Returns the last day of the month in the specified date.

Behavior type

Immutable if the specified is a TIMESTAMP or DATE
Stable if the specified date is a TIMESTAMPTZ

Syntax

LAST_DAY ( date )

Parameters

date

The date to process, one of the following data types:

Calculating first day of month

SQL does not support any function that returns the first day in the month of a given date. You must use other functions to work around this limitation. For example:

=> SELECT DATE ('2022/07/04') - DAYOFMONTH ('2022/07/04') +1;
  ?column?
------------
 2022-07-01
(1 row)

=> SELECT LAST_DAY('1929/06/06') - (SELECT DAY(LAST_DAY('1929/06/06'))-1);
  ?column?
------------
 1929-06-01
(1 row)

Examples

The following example returns the last day of February as 29 because 2016 is a leap year:

=> SELECT LAST_DAY('2016-02-28 23:30 PST') "Last Day";
  Last Day
------------
 2016-02-29
(1 row)

The following example returns the last day of February in a non-leap year:

> SELECT LAST_DAY('2017/02/03') "Last";
    Last
------------
 2017-02-28
(1 row)

The following example returns the last day of March, after converting the string value to the specified DATE type:

=> SELECT LAST_DAY('2003/03/15') "Last";
    Last
------------
 2012-03-31
(1 row)

25 - LOCALTIME

Returns a value of type TIME that represents the start of the current transaction.

Returns a value of type TIME that represents the start of the current transaction.

The return value does not change during the transaction. Thus, multiple calls to LOCALTIME within the same transaction return the same timestamp.

Behavior type

Stable

Syntax

LOCALTIME [ ( precision ) ]

Parameters

precision: Rounds the result to the specified number of fractional digits in the seconds field.

Examples

=> CREATE TABLE t1 (a int, b int);
CREATE TABLE

=> INSERT INTO t1 VALUES (1,2);
 OUTPUT
--------
      1
(1 row)

=> SELECT LOCALTIME time;
    time
-----------------
 15:03:14.595296
(1 row)

=> INSERT INTO t1 VALUES (3,4);
 OUTPUT
--------
      1
(1 row)

=> SELECT LOCALTIME;
    time
-----------------
 15:03:14.595296
(1 row)

=> COMMIT;
COMMIT
=> SELECT LOCALTIME;
    time
-----------------
 15:03:49.738032
(1 row)

26 - LOCALTIMESTAMP

Returns a value of type TIMESTAMP/TIMESTAMPTZ that represents the start of the current transaction, and remains unchanged until the transaction is closed.

Returns a value of type TIMESTAMP/TIMESTAMPTZ that represents the start of the current transaction, and remains unchanged until the transaction is closed. Thus, multiple calls to LOCALTIMESTAMP within a given transaction return the same timestamp.

Behavior type

Stable

Syntax

LOCALTIMESTAMP [ ( precision ) ]

Parameters

precision: Rounds the result to the specified number of fractional digits in the seconds field.

Examples

=> CREATE TABLE t1 (a int, b int);
CREATE TABLE
=> INSERT INTO t1 VALUES (1,2);
 OUTPUT
--------
      1
(1 row)

=> SELECT LOCALTIMESTAMP(2) AS 'local timestamp';
    local timestamp
------------------------
 2021-03-05 10:48:58.26
(1 row)

=> INSERT INTO t1 VALUES (3,4);
 OUTPUT
--------
      1
(1 row)

=> SELECT LOCALTIMESTAMP(2) AS 'local timestamp';
    local timestamp
------------------------
 2021-03-05 10:48:58.26
(1 row)

=> COMMIT;
COMMIT
=> SELECT LOCALTIMESTAMP(2) AS 'local timestamp';
    local timestamp
------------------------
 2021-03-05 10:50:08.99
(1 row)

27 - MICROSECOND

Returns the microsecond portion of the specified date as an integer.

Behavior type

Immutable if thespecified date is a TIMESTAMP, INTERVAL, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

MICROSECOND ( date )

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT MICROSECOND (TIMESTAMP 'Sep 22, 2011 12:34:01.123456');
 MICROSECOND
-------------
      123456
(1 row)

28 - MIDNIGHT_SECONDS

Within the specified date, returns the number of seconds between midnight and the date's time portion.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

MIDNIGHT_SECONDS ( date )

Parameters

date

The date to process, one of the following data types:

Examples

Get the number of seconds since midnight:

=> SELECT MIDNIGHT_SECONDS(CURRENT_TIMESTAMP);
 MIDNIGHT_SECONDS
------------------
            36480
(1 row)

Get the number of seconds between midnight and noon on March 3 2016:

=> SELECT MIDNIGHT_SECONDS('3-3-2016 12:00'::TIMESTAMP);
 MIDNIGHT_SECONDS
------------------
            43200
(1 row)

29 - MINUTE

Returns the minute portion of the specified date as an integer.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, VARCHAR or INTERVAL
Stable if the specified date is aTIMESTAMPTZ

Syntax

MINUTE ( date )

Parameters

date

The date to process, one of the following data types:

INTERVAL

Examples

=> SELECT MINUTE('12:34:03.456789');
 MINUTE
--------
     34
(1 row)
=>SELECT MINUTE (TIMESTAMP 'sep 22, 2011 12:34');
 MINUTE
--------
     34
(1 row)
=> SELECT MINUTE(INTERVAL '35 12:34:03.456789');
 MINUTE
--------
     34
(1 row)

30 - MONTH

Returns the month portion of the specified date as an integer.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, VARCHAR or INTERVAL
Stable if the specified date is aTIMESTAMPTZ

Syntax

MONTH ( date )

Parameters

date

The date to process, one of the following data types:

INTERVAL

Examples

In the following examples, Vertica returns the month portion of the specified string. For example, '6-9' represent September 6.

=> SELECT MONTH('6-9');
 MONTH
-------
     9
(1 row)
=> SELECT MONTH (TIMESTAMP 'sep 22, 2011 12:34');
 MONTH
-------
     9
(1 row)
=> SELECT MONTH(INTERVAL '2-35' year to month);
 MONTH
-------
    11
(1 row)

31 - MONTHS_BETWEEN

Returns the number of months between two dates.

Returns the number of months between two dates. MONTHS_BETWEEN can return an integer or a FLOAT:

Integer: The day portions of date1 and date2 are the same, and neither date is the last day of the month. MONTHS_BETWEEN also returns an integer if both dates in date1 and date2 are the last days of their respective months. For example, MONTHS_BETWEEN calculates the difference between April 30 and March 31 as 1 month.
FLOAT: The day portions of date1 and date2 are different and one or both dates are not the last day of their respective months. For example, the difference between April 2 and March 1 is 1.03225806451613. To calculate month fractions, MONTHS_BETWEEN assumes all months contain 31 days.

MONTHS_BETWEEN disregards timestamp time portions.

Behavior type

Immutable if both date arguments are of data type TIMESTAMP or DATE
Stable if either date is a TIMESTAMPTZ

Syntax

MONTHS_BETWEEN ( date1 , date2 );

Parameters

date1 date2

Specify the dates to evaluate where date1 and date2 evaluate to one of the following data types:

DATE
TIMESTAMP
TIMESTAMPTZ

If date1 < date2, MONTHS_BETWEEN returns a negative value.

Examples

Return the number of months between April 7 2016 and January 7 2015:

=> SELECT MONTHS_BETWEEN ('04-07-16'::TIMESTAMP, '01-07-15'::TIMESTAMP);
 MONTHS_BETWEEN
----------------
             15
(1 row)

Return the number of months between March 31 2016 and February 28 2016 (MONTHS_BETWEEN assumes both months contain 31 days):

=> SELECT MONTHS_BETWEEN ('03-31-16'::TIMESTAMP, '02-28-16'::TIMESTAMP);
  MONTHS_BETWEEN
------------------
 1.09677419354839
(1 row)

Return the number of months between March 31 2016 and February 29 2016:

=> SELECT MONTHS_BETWEEN ('03-31-16'::TIMESTAMP, '02-29-16'::TIMESTAMP);
 MONTHS_BETWEEN
----------------
              1
(1 row)

32 - NEW_TIME

Converts a timestamp value from one time zone to another and returns a TIMESTAMP.

Behavior type

Immutable

Syntax

NEW_TIME( 'timestamp' , 'timezone1' , 'timezone2')

Parameters

timestamp

The timestamp to convert, conforms to one of the following formats:

TIMESTAMP/ TIMESTAMPTZ
DATE
Character string that can be converted to a TIMESTAMP—for example, May 24, 2012 10:00.

timezone1 *timezone2*

Specify the source and target timezones, one of the strings defined in /opt/vertica/share/timezonesets. For example:

GMT: Greenwich Mean Time
AST / ADT: Atlantic Standard/Daylight Time
EST / EDT: Eastern Standard/Daylight Time
CST / CDT: Central Standard/Daylight Time
MST / MDT: Mountain Standard/Daylight Time
PST / PDT: Pacific Standard/Daylight Time

Examples

Convert the specified time from Eastern Standard Time (EST) to Pacific Standard Time (PST):

=> SELECT NEW_TIME('05-24-12 13:48:00', 'EST', 'PST');
      NEW_TIME
---------------------
 2012-05-24 10:48:00
(1 row)

Convert 1:00 AM January 2012 from EST to PST:

=> SELECT NEW_TIME('01-01-12 01:00:00', 'EST', 'PST');
      NEW_TIME
---------------------
 2011-12-31 22:00:00
(1 row)

Convert the current time EST to PST:


=> SELECT NOW();
              NOW
-------------------------------
 2016-12-09 10:30:36.727307-05
(1 row)

=> SELECT NEW_TIME('NOW', 'EDT', 'CDT');
          NEW_TIME
----------------------------
 2016-12-09 09:30:36.727307
(1 row)

The following example returns the year 45 before the Common Era in Greenwich Mean Time and converts it to Newfoundland Standard Time:

=>  SELECT NEW_TIME('April 1, 45 BC', 'GMT', 'NST')::DATE;
   NEW_TIME
---------------
 0045-03-31 BC
(1 row)

33 - NEXT_DAY

Returns the date of the first instance of a particular day of the week that follows the specified date.

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Syntax

NEXT_DAY( 'date', 'day-string')

Parameters

date

The date to process, one of the following data types:

day-string

The day of the week to process, a CHAR or VARCHAR string or character constant. Supply the full English name such as Tuesday, or any conventional abbreviation, such as Tue or Tues. day-string is not case sensitive and trailing spaces are ignored.

Examples

Get the date of the first Monday that follows April 29 2016:

=> SELECT NEXT_DAY('4-29-2016'::TIMESTAMP,'Monday') "NEXT DAY" ;
  NEXT DAY
------------
 2016-05-02
(1 row)

Get the first Tuesday that follows today:

SELECT NEXT_DAY(CURRENT_TIMESTAMP,'tues') "NEXT DAY" ;
  NEXT DAY
------------
 2016-05-03
(1 row)

34 - NOW [date/time]

Returns a value of type TIMESTAMP WITH TIME ZONE representing the start of the current transaction.

Returns a value of type TIMESTAMP WITH TIME ZONE representing the start of the current transaction. NOW is equivalent to CURRENT_TIMESTAMP except that it does not accept a precision parameter.

The return value does not change during the transaction. Thus, multiple calls to CURRENT_TIMESTAMP within the same transaction return the same timestamp.

Behavior type

Stable

Syntax

NOW()

Examples


=> CREATE TABLE t1 (a int, b int);
CREATE TABLE
=> INSERT INTO t1 VALUES (1,2);
 OUTPUT
--------
      1
(1 row)

=> SELECT NOW();
             NOW
------------------------------
 2016-12-09 13:00:08.74685-05
(1 row)

=> INSERT INTO t1 VALUES (3,4);
 OUTPUT
--------
      1
(1 row)

=> SELECT NOW();
             NOW
------------------------------
 2016-12-09 13:00:08.74685-05
(1 row)

=> COMMIT;
COMMIT
dbadmin=> SELECT NOW();
              NOW
-------------------------------
 2016-12-09 13:01:31.420624-05
(1 row)

35 - OVERLAPS

Evaluates two time periods and returns true when they overlap, false otherwise.

Behavior type

Stable when TIMESTAMP and TIMESTAMPTZ are both used, or when TIMESTAMPTZ is used with INTERVAL
Immutable otherwise

Syntax

( start, end ) OVERLAPS ( start, end )
( start, interval) OVERLAPS ( start, interval )

Parameters

start: DATE, TIME, or TIMESTAMP/TIMESTAMPTZ value that specifies the beginning of a time period.
end: DATE, TIME, or TIMESTAMP/TIMESTAMPTZ value that specifies the end of a time period.
interval: Value that specifies the length of the time period.

Examples

Evaluate whether date ranges Feb 16 - Dec 21, 2016 and Oct 10 2008 - Oct 3 2016 overlap:

=> SELECT (DATE '2016-02-16', DATE '2016-12-21') OVERLAPS (DATE '2008-10-30', DATE '2016-10-30');
 overlaps
----------
 t
(1 row)

Evaluate whether date ranges Feb 16 - Dec 21, 2016 and Jan 01 - Oct 30 2008 - Oct 3, 2016 overlap:

=> SELECT (DATE '2016-02-16', DATE '2016-12-21') OVERLAPS (DATE '2008-01-30', DATE '2008-10-30');
 overlaps
----------
 f
(1 row)

Evaluate whether date range Feb 02 2016 + 1 week overlaps with date range Oct 16 2016 - 8 months:

=> SELECT (DATE '2016-02-16', INTERVAL '1 week') OVERLAPS (DATE '2016-10-16', INTERVAL '-8 months');
 overlaps
----------
 t
(1 row)

36 - QUARTER

Returns calendar quarter of the specified date as an integer, where the January-March quarter is 1.

Syntax

QUARTER ( date )

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR.
Stable if the specified date is aTIMESTAMPTZ

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT QUARTER (TIMESTAMP 'sep 22, 2011 12:34');
 QUARTER
---------
       3
(1 row)

37 - ROUND

Rounds the specified date or time.

Rounds the specified date or time. If you omit the precision argument, ROUND rounds to day (DD) precision.

Behavior type

Immutable if thetarget date is a TIMESTAMP or DATE
Stable if the target date is aTIMESTAMPTZ

Syntax

ROUND( `*`rounding-target`*`[, 'precision'] )

Parameters

*rounding-target*

An expression that evaluates to one of the following data types:

precision

A string constant that specifies precision for the rounded value, one of the following:

Century: CC | SCC
Year: SYYY | YYYY | YEAR | YYY | YY | Y
ISO Year: IYYY | IYY | IY | I
Quarter: Q
Month: MONTH | MON | MM | RM
Same weekday as first day of year: WW
Same weekday as first day of ISO year: IW
Same weekday as first day of month: W
Day (default): DDD | DD | J
First weekday: DAY | DY | D
Hour: HH | HH12 | HH24
Minute: MI
Second: SS

Note

Hour, minute, and second rounding is not supported by DATE expressions.

Examples

Round to the nearest hour:

=> SELECT ROUND(CURRENT_TIMESTAMP, 'HH');
        ROUND
---------------------
 2016-04-28 15:00:00
(1 row)

Round to the nearest month:

=> SELECT ROUND('9-22-2011 12:34:00'::TIMESTAMP, 'MM');
        ROUND
---------------------
 2011-10-01 00:00:00
(1 row)

38 - SECOND

Returns the seconds portion of the specified date as an integer.

Syntax

SECOND ( date )

Behavior type

Immutable, except for TIMESTAMPTZ arguments where it is stable.

Parameters

date

The date to process, one of the following data types:

Examples

=> SELECT SECOND ('23:34:03.456789');
 SECOND
--------
      3
(1 row)
=> SELECT SECOND (TIMESTAMP 'sep 22, 2011 12:34');
 SECOND
--------
      0
(1 row)
=> SELECT SECOND (INTERVAL '35 12:34:03.456789');
 SECOND
--------
      3
(1 row)

39 - STATEMENT_TIMESTAMP

Similar to TRANSACTION_TIMESTAMP, returns a value of type TIMESTAMP WITH TIME ZONE that represents the start of the current statement.

Similar to TRANSACTION_TIMESTAMP, returns a value of type TIMESTAMP WITH TIME ZONE that represents the start of the current statement.

The return value does not change during statement execution. Thus, different stages of statement execution always have the same timestamp.

Behavior type

Stable

Syntax

STATEMENT_TIMESTAMP()

Examples

=> SELECT foo, bar FROM (SELECT STATEMENT_TIMESTAMP() AS foo)foo, (SELECT STATEMENT_TIMESTAMP() as bar)bar;
              foo              |              bar
-------------------------------+-------------------------------
 2016-12-07 14:55:51.543988-05 | 2016-12-07 14:55:51.543988-05
(1 row)

40 - SYSDATE

Returns the current statement's start date and time as a TIMESTAMP value.

Returns the current statement's start date and time as a TIMESTAMP value. This function is identical to GETDATE.

SYSDATE uses the date and time supplied by the operating system on the server to which you are connected, which is the same across all servers. Internally, GETDATE converts STATEMENT_TIMESTAMP from TIMESTAMPTZ to TIMESTAMP.

Behavior type

Stable

Syntax

SYSDATE()

Note

You can call this function with no parentheses.

Examples

=> SELECT SYSDATE;
          sysdate
----------------------------
 2016-12-12 06:11:10.699642
(1 row)

41 - TIME_SLICE

Aggregates data by different fixed-time intervals and returns a rounded-up input TIMESTAMP value to a value that corresponds with the start or end of the time slice interval.

Aggregates data by different fixed-time intervals and returns a rounded-up input TIMESTAMP value to a value that corresponds with the start or end of the time slice interval.

Given an input TIMESTAMP value such as 2000-10-28 00:00:01, the start time of a 3-second time slice interval is 2000-10-28 00:00:00, and the end time of the same time slice is 2000-10-28 00:00:03.

Behavior type

Immutable

Syntax

TIME_SLICE( expression, slice-length [, 'time-unit' [, 'start-or-end' ] ] )

Parameters

expression

One of the following:

Column of type TIMESTAMP
String constant that can be parsed into a TIMESTAMP value. For example:

'2004-10-19 10:23:54'

Vertica evaluates expression on each row.

slice-length

A positive integer that specifies the slice length.

time-unit

Time unit of the slice, one of the following:

HOUR
MINUTE
SECOND (default)
MILLISECOND
MICROSECOND

start-or-end

Specifies whether the returned value corresponds to the start or end time with one of the following strings:

START (default)
END

Note

This parameter can be included only if you also supply a non-null time-unit argument.

Null argument handling

TIME_SLICE handles null arguments as follows:

TIME_SLICE returns an error when any one of slice-length, time-unit, or start-or-end parameters is null.
If expression is null and slice-length, time-unit, or start-or-end contain legal values, TIME_SLICE returns a NULL value instead of an error.

Usage

The following command returns the (default) start time of a 3-second time slice:

=> SELECT TIME_SLICE('2009-09-19 00:00:01', 3);
     TIME_SLICE
---------------------
 2009-09-19 00:00:00
(1 row)

The following command returns the end time of a 3-second time slice:

=> SELECT TIME_SLICE('2009-09-19 00:00:01', 3, 'SECOND', 'END');
     TIME_SLICE
---------------------
 2009-09-19 00:00:03
(1 row)

This command returns results in milliseconds, using a 3-second time slice:

=> SELECT TIME_SLICE('2009-09-19 00:00:01', 3, 'ms');
       TIME_SLICE
-------------------------
 2009-09-19 00:00:00.999

(1 row)

This command returns results in microseconds, using a 9-second time slice:

=> SELECT TIME_SLICE('2009-09-19 00:00:01', 3, 'us');
         TIME_SLICE
----------------------------
 2009-09-19 00:00:00.999999
(1 row)

The next example uses a 3-second interval with an input value of '00:00:01'. To focus specifically on seconds, the example omits date, though all values are implied as being part of the timestamp with a given input of '00:00:01':

'00:00:00' is the start of the 3-second time slice
'00:00:03' is the end of the 3-second time slice.
'00:00:03' is also the start of the second 3-second time slice. In time slice boundaries, the end value of a time slice does not belong to that time slice; it starts the next one.

When the time slice interval is not a factor of 60 seconds, such as a given slice length of 9 in the following example, the slice does not always start or end on 00 seconds:

=> SELECT TIME_SLICE('2009-02-14 20:13:01', 9);
     TIME_SLICE
---------------------
 2009-02-14 20:12:54
(1 row)

This is expected behavior, as the following properties are true for all time slices:

Equal in length
Consecutive (no gaps between them)
Non-overlapping

To force the above example ('2009-02-14 20:13:01') to start at '2009-02-14 20:13:00', adjust the output timestamp values so that the remainder of 54 counts up to 60:

=> SELECT TIME_SLICE('2009-02-14 20:13:01', 9 )+'6 seconds'::INTERVAL AS time;
        time
---------------------
 2009-02-14 20:13:00
(1 row)

Alternatively, you could use a different slice length, which is divisible by 60, such as 5:

=> SELECT TIME_SLICE('2009-02-14 20:13:01', 5);
     TIME_SLICE
---------------------
 2009-02-14 20:13:00
(1 row)

A TIMESTAMPTZ value is implicitly cast to TIMESTAMP. For example, the following two statements have the same effect.

=> SELECT TIME_SLICE('2009-09-23 11:12:01'::timestamptz, 3);
     TIME_SLICE
---------------------
 2009-09-23 11:12:00
(1 row)


=> SELECT TIME_SLICE('2009-09-23 11:12:01'::timestamptz::timestamp, 3);

     TIME_SLICE
---------------------
 2009-09-23 11:12:00
(1 row)

Examples

You can use the SQL analytic functions FIRST_VALUE and LAST_VALUE to find the first/last price within each time slice group (set of rows belonging to the same time slice). This structure can be useful if you want to sample input data by choosing one row from each time slice group.

=> SELECT date_key, transaction_time, sales_dollar_amount,TIME_SLICE(DATE '2000-01-01' + date_key + transaction_time, 3),
FIRST_VALUE(sales_dollar_amount)
OVER (PARTITION BY TIME_SLICE(DATE '2000-01-01' + date_key + transaction_time, 3)
     ORDER BY DATE '2000-01-01' + date_key + transaction_time) AS first_value
FROM store.store_sales_fact
LIMIT 20;

 date_key | transaction_time | sales_dollar_amount |     time_slice      | first_value
----------+------------------+---------------------+---------------------+-------------
        1 | 00:41:16         |                 164 | 2000-01-02 00:41:15 |         164
        1 | 00:41:33         |                 310 | 2000-01-02 00:41:33 |         310
        1 | 15:32:51         |                 271 | 2000-01-02 15:32:51 |         271
        1 | 15:33:15         |                 419 | 2000-01-02 15:33:15 |         419
        1 | 15:33:44         |                 193 | 2000-01-02 15:33:42 |         193
        1 | 16:36:29         |                 466 | 2000-01-02 16:36:27 |         466
        1 | 16:36:44         |                 250 | 2000-01-02 16:36:42 |         250
        2 | 03:11:28         |                  39 | 2000-01-03 03:11:27 |          39
        3 | 03:55:15         |                 375 | 2000-01-04 03:55:15 |         375
        3 | 11:58:05         |                 369 | 2000-01-04 11:58:03 |         369
        3 | 11:58:24         |                 174 | 2000-01-04 11:58:24 |         174
        3 | 11:58:52         |                 449 | 2000-01-04 11:58:51 |         449
        3 | 19:01:21         |                 201 | 2000-01-04 19:01:21 |         201
        3 | 22:15:05         |                 156 | 2000-01-04 22:15:03 |         156
        4 | 13:36:57         |                -125 | 2000-01-05 13:36:57 |        -125
        4 | 13:37:24         |                -251 | 2000-01-05 13:37:24 |        -251
        4 | 13:37:54         |                 353 | 2000-01-05 13:37:54 |         353
        4 | 13:38:04         |                 426 | 2000-01-05 13:38:03 |         426
        4 | 13:38:31         |                 209 | 2000-01-05 13:38:30 |         209
        5 | 10:21:24         |                 488 | 2000-01-06 10:21:24 |         488
(20 rows)

TIME_SLICE rounds the transaction time to the 3-second slice length.

The following example uses the analytic (window) OVER clause to return the last trading price (the last row ordered by TickTime) in each 3-second time slice partition:

=> SELECT DISTINCT TIME_SLICE(TickTime, 3), LAST_VALUE(price)OVER (PARTITION BY TIME_SLICE(TickTime, 3)
ORDER BY TickTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING);

Note

If you omit the windowing clause from an analytic clause, LAST_VALUE defaults to RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW. Results can seem non-intuitive, because instead of returning the value from the bottom of the current partition, the function returns the bottom of the window, which continues to change along with the current input row that is being processed. For more information, see Time series analytics and SQL analytics.

In the next example, FIRST_VALUE is evaluated once for each input record and the data is sorted by ascending values. Use SELECT DISTINCT to remove the duplicates and return only one output record per TIME_SLICE:

=> SELECT DISTINCT TIME_SLICE(TickTime, 3), FIRST_VALUE(price)OVER (PARTITION BY TIME_SLICE(TickTime, 3)
ORDER BY TickTime ASC)
FROM tick_store;
     TIME_SLICE      | ?column?
---------------------+----------
 2009-09-21 00:00:06 |    20.00
 2009-09-21 00:00:09 |    30.00
 2009-09-21 00:00:00 |    10.00
(3 rows)

The information output by the above query can also return MIN, MAX, and AVG of the trading prices within each time slice.

=> SELECT DISTINCT TIME_SLICE(TickTime, 3),FIRST_VALUE(Price) OVER (PARTITION BY TIME_SLICE(TickTime, 3)
ORDER BY TickTime ASC),
  MIN(price) OVER (PARTITION BY TIME_SLICE(TickTime, 3)),
  MAX(price) OVER (PARTITION BY TIME_SLICE(TickTime, 3)),
  AVG(price) OVER (PARTITION BY TIME_SLICE(TickTime, 3))
FROM tick_store;

42 - TIMEOFDAY

Returns the wall-clock time as a text string.

Returns the wall-clock time as a text string. Function results advance during transactions.

Behavior type

Volatile

Syntax

TIMEOFDAY()

Examples

=> SELECT TIMEOFDAY();
              TIMEOFDAY
-------------------------------------
 Mon Dec 12 08:18:01.022710 2016 EST
(1 row)

43 - TIMESTAMP_ROUND

Rounds the specified TIMESTAMP.

Rounds the specified TIMESTAMP. If you omit the precision argument, TIMESTAMP_ROUND rounds to day (DD) precision.

Behavior type

Immutable if thetarget date is a TIMESTAMP
Stable if the target date is a TIMESTAMPTZ

Syntax

TIMESTAMP_ROUND ( rounding-target[, 'precision'] )

Parameters

rounding-target

An expression that evaluates to one of the following data types:

TIMESTAMP/TIMESTAMPTZ
TIMESTAMPTZ

precision

A string constant that specifies precision for the rounded value, one of the following:

Century: CC | SCC
Year: SYYY | YYYY | YEAR | YYY | YY | Y
ISO Year: IYYY | IYY | IY | I
Quarter: Q
Month: MONTH | MON | MM | RM
Same weekday as first day of year: WW
Same weekday as first day of ISO year: IW
Same weekday as first day of month: W
Day (default): DDD | DD | J
First weekday: DAY | DY | D
Hour: HH | HH12 | HH24
Minute: MI
Second: SS

Note

Hour, minute, and second rounding is not supported by DATE expressions.

Examples

Round to the nearest hour:

=> SELECT TIMESTAMP_ROUND(CURRENT_TIMESTAMP, 'HH');
        ROUND
---------------------
 2016-04-28 15:00:00
(1 row)

Round to the nearest month:

=> SELECT TIMESTAMP_ROUND('9-22-2011 12:34:00'::TIMESTAMP, 'MM');
        ROUND
---------------------
 2011-10-01 00:00:00
(1 row)

44 - TIMESTAMP_TRUNC

Truncates the specified TIMESTAMP.

Truncates the specified TIMESTAMP. If you omit the precision argument, TIMESTAMP_TRUNC truncates to day (DD) precision.

Behavior type

Immutable if thetarget date is a TIMESTAMP
Stable if the target date is a TIMESTAMPTZ

Syntax

TIMESTAMP_TRUNC( trunc-target[, 'precision'] )

Parameters

trunc-target

An expression that evaluates to one of the following data types:

TIMESTAMP/TIMESTAMPTZ
TIMESTAMPTZ

precision

A string constant that specifies precision for the truncated value, one of the following:

Century: CC | SCC
Year: SYYY | YYYY | YEAR | YYY | YY | Y
ISO Year: IYYY | IYY | IY | I
Quarter: Q
Month: MONTH | MON | MM | RM
Same weekday as first day of year: WW
Same weekday as first day of ISO year: IW
Same weekday as first day of month: W
Day: DDD | DD | J
First weekday: DAY | DY | D
Hour: HH | HH12 | HH24
Minute: MI
Second: SS

Note

Hour, minute, and second truncating is not supported by DATE expressions.

Examples

Truncate to the current hour:

=> SELECT TIMESTAMP_TRUNC(CURRENT_TIMESTAMP, 'HH');
   TIMESTAMP_TRUNC
---------------------
 2016-04-29 08:00:00
(1 row)

Truncate to the month:

=> SELECT TIMESTAMP_TRUNC('9-22-2011 12:34:00'::TIMESTAMP, 'MM');
   TIMESTAMP_TRUNC
---------------------
 2011-09-01 00:00:00
(1 row)

45 - TIMESTAMPADD

Adds the specified number of intervals to a TIMESTAMP or TIMESTAMPTZ value and returns a result of the same data type.

Behavior type

Immutable if the input date is a TIMESTAMP
Stable if the input date is a TIMESTAMPTZ

Syntax

TIMESTAMPADD ( datepart, count, start-date );

Parameters

datepart

Specifies the type of time intervals that TIMESTAMPADD adds to the specified start date. If datepart is an expression, it must be enclosed in parentheses:

TIMESTAMPADD((expression), `*`interval`*`, `*`start`*`;

datepart must evaluate to one of the following string literals, either quoted or unquoted:

year | yy | yyyy
quarter | qq | q
month | mm | m
day | dayofyear | dd | d | dy | y
week | wk | ww
hour | hh
minute | mi | n
second | ss | s
millisecond | ms
microsecond | mcs | us

count

Integer or integer expression that specifies the number of datepart intervals to add to start-date.

start-date

TIMESTAMP or TIMESTAMPTZ value.

Examples

Add two months to the current date:

=> SELECT CURRENT_TIMESTAMP AS Today;
           Today
-------------------------------
 2016-05-02 06:56:57.923045-04
(1 row)

=> SELECT TIMESTAMPADD (MONTH, 2, (CURRENT_TIMESTAMP)) AS TodayPlusTwoMonths;;
      TodayPlusTwoMonths
-------------------------------
 2016-07-02 06:56:57.923045-04
(1 row)

Add 14 days to the beginning of the current month:

=> SELECT TIMESTAMPADD (DD, 14, (SELECT TRUNC((CURRENT_TIMESTAMP), 'MM')));
    timestampadd
---------------------
 2016-05-15 00:00:00
(1 row)

46 - TIMESTAMPDIFF

Returns the time span between two TIMESTAMP or TIMESTAMPTZ values, in the intervals specified.

Returns the time span between two TIMESTAMP or TIMESTAMPTZ values, in the intervals specified. TIMESTAMPDIFF excludes the start date in its calculation.

Behavior type

Immutable if start and end dates are TIMESTAMP
Stable if start and end dates are TIMESTAMPTZ

Syntax

TIMESTAMPDIFF ( datepart, start, end );

Parameters

datepart

Specifies the type of date or time intervals that TIMESTAMPDIFF returns. If datepart is an expression, it must be enclosed in parentheses:

TIMESTAMPDIFF((expression), start, end );

datepart must evaluate to one of the following string literals, either quoted or unquoted:

year | yy | yyyy
quarter | qq | q
month | mm | m
day | dayofyear | dd | d | dy | y
week | wk | ww
hour | hh
minute | mi | n
second | ss | s
millisecond | ms
microsecond | mcs | us

start, end

Specify the start and end dates, where start and end evaluate to one of the following data types:

TIMESTAMP/TIMESTAMPTZ
TIMESTAMPTZ

If end < start, TIMESTAMPDIFF returns a negative value.

Date part intervals

TIMESTAMPDIFF uses the datepart argument to calculate the number of intervals between two dates, rather than the actual amount of time between them. For detailed information, see DATEDIFF.

Examples

=> SELECT TIMESTAMPDIFF (YEAR,'1-1-2006 12:34:00', '1-1-2008 12:34:00');
 timestampdiff
---------------
             2
(1 row)

47 - TRANSACTION_TIMESTAMP

Returns a value of type that represents the start of the current transaction.

Returns a value of type TIME WITH TIMEZONE that represents the start of the current transaction.

The return value does not change during the transaction. Thus, multiple calls to TRANSACTION_TIMESTAMP within the same transaction return the same timestamp.

TRANSACTION_TIMESTAMP is equivalent to CURRENT_TIMESTAMP, except it does not accept a precision parameter.

Behavior type

Stable

Syntax

TRANSACTION_TIMESTAMP()

Examples

=> SELECT foo, bar FROM (SELECT TRANSACTION_TIMESTAMP() AS foo)foo, (SELECT TRANSACTION_TIMESTAMP() as bar)bar;
              foo              |              bar
-------------------------------+-------------------------------
 2016-12-12 08:18:00.988528-05 | 2016-12-12 08:18:00.988528-05
(1 row)

48 - TRUNC

Truncates the specified date or time.

Truncates the specified date or time. If you omit the precision argument, TRUNC truncates to day (DD) precision.

Behavior type

Immutable if thetarget date is a TIMESTAMP or DATE
Stable if the target date is aTIMESTAMPTZ

Syntax

TRUNC( trunc-target[, 'precision'] )

Parameters

*trunc-target*

An expression that evaluates to one of the following data types:

precision

A string constant that specifies precision for the truncated value, one of the following:

Century: CC | SCC
Year: SYYY | YYYY | YEAR | YYY | YY | Y
ISO Year: IYYY | IYY | IY | I
Quarter: Q
Month: MONTH | MON | MM | RM
Same weekday as first day of year: WW
Same weekday as first day of ISO year: IW
Same weekday as first day of month: W
Day (default): DDD | DD | J
First weekday: DAY | DY | D
Hour: HH | HH12 | HH24
Minute: MI
Second: SS

Note

Hour, minute, and second truncating is not supported by DATE expressions.

Examples

Truncate to the current hour:

=> => SELECT TRUNC(CURRENT_TIMESTAMP, 'HH');
        TRUNC
---------------------
 2016-04-29 10:00:00
(1 row)

Truncate to the month:

=> SELECT TRUNC('9-22-2011 12:34:00'::TIMESTAMP, 'MM');
   TIMESTAMP_TRUNC
---------------------
 2011-09-01 00:00:00
(1 row)

49 - WEEK

Returns the week of the year for the specified date as an integer, where the first week begins on the first Sunday on or preceding January 1.

Syntax

WEEK ( date )

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Parameters

date

The date to process, one of the following data types:

Examples

January 2 is on Saturday, so WEEK returns 1:

=> SELECT WEEK ('1-2-2016'::DATE);
 WEEK
------
    1
(1 row)

January 3 is the second Sunday in 2016, so WEEK returns 2:

=> SELECT WEEK ('1-3-2016'::DATE);
 WEEK
------
    2
(1 row)

50 - WEEK_ISO

Returns the week of the year for the specified date as an integer, where the first week starts on Monday and contains January 4.

Returns the week of the year for the specified date as an integer, where the first week starts on Monday and contains January 4. This function conforms with the ISO 8061 standard.

Syntax

WEEK_ISO ( date )

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Parameters

date

The date to process, one of the following data types:

Examples

The first week of 2016 begins on Monday January 4:

=> SELECT WEEK_ISO ('1-4-2016'::DATE);
 WEEK_ISO
----------
        1
(1 row)

January 3 2016 returns week 53 of the previous year (2015):

=> SELECT WEEK_ISO ('1-3-2016'::DATE);
 WEEK_ISO
----------
       53
(1 row)

In 2015, January 4 is on Sunday, so the first week of 2015 begins on the preceding Monday (December 29 2014):

=> SELECT WEEK_ISO ('12-29-2014'::DATE);
 WEEK_ISO
----------
        1
(1 row)

51 - YEAR

Returns an integer that represents the year portion of the specified date.

Syntax

YEAR( date )

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, VARCHAR, or INTERVAL
Stable if the specified date is aTIMESTAMPTZ

Parameters

date

The date to process, one of the following data types:

INTERVAL

Examples

=> SELECT YEAR(CURRENT_DATE::DATE);
 YEAR
------
 2016
(1 row)

52 - YEAR_ISO

Returns an integer that represents the year portion of the specified date.

Returns an integer that represents the year portion of the specified date. The return value is based on the ISO 8061 standard.

The first week of the ISO year is the week that contains January 4.

Syntax

YEAR_ISO ( date )

Behavior type

Immutable if thespecified date is a TIMESTAMP, DATE, or VARCHAR
Stable if the specified date is aTIMESTAMPTZ

Parameters

date

The date to process, one of the following data types:

Examples

> SELECT YEAR_ISO(CURRENT_DATE::DATE);
 YEAR_ISO
----------
     2016
(1 row)

Date/time functions

Usage

Daylight savings time considerations

Date/time functions in transactions

See also

1 - ADD_MONTHS

Behavior type

Syntax

Parameters

Examples

2 - AGE_IN_MONTHS

Behavior type

Syntax

Parameters

Examples

3 - AGE_IN_YEARS

Behavior type

Syntax

Parameters

Examples

4 - CLOCK_TIMESTAMP

Behavior type

Syntax

Examples

See also

5 - CURRENT_DATE

Behavior type

Syntax

Note

Examples

6 - CURRENT_TIME

Behavior type

Syntax

Note

Parameters

Examples

7 - CURRENT_TIMESTAMP

Behavior type

Syntax

Parameters

Examples

8 - DATE

Behavior type

Syntax

Parameters

Examples

See also

9 - DATE_PART

Behavior type

Syntax

Parameters

Field values

Note

Notes

Examples

See also

10 - DATE_TRUNC

Behavior type

Syntax

Parameters

Precision field values

Examples

11 - DATEDIFF

Behavior type

Syntax

Parameters

Note

Compatible start and end date data types

Date part intervals

See also

12 - DAY

Behavior type

Syntax

Parameters

Examples

13 - DAYOFMONTH

Behavior type

Syntax

Parameters

Examples