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8 PostgreSQL Date and Time Function Examples

In this article, let us review following PostgreSQL date and time functions with practical examples.

  • now()
  • now()::date
  • now()::time
  • date_part()
  • age()
  • extract()
  • date_trunc()
  • to_char()
  • to_timestamp()

1. Get Current Date and Time using PostgreSQL now()

Get current date and time using the following query.

dbase=# select now();
 2010-06-19 09:28:43.98216-07
(1 row)

Use the ::time as shown below to get only the time (without date).

dbase=# select now()::time;
(1 row)

Use the ::date as shown below to get only the date (without time).

dbase=# select now()::date;
(1 row)

2. Get Interval Between Two PostgreSQL Dates

In order to get the number of days between two dates, use the ‘-‘ operator. This works like an arithmetic operator.

Let us assume that the employee table contains following records.

# select name,date_of_join from employee;
   name  | date_of_join
 Neeraj | 2002-11-23
 Kiran  | 2003-01-01
 Sam    | 2005-11-23
 John   | 2006-01-01
(4 rows)

Following examples displays number of days between the current date and date_of_join of employees.

dbase=#  select now() - date_of_join as days from employee ;
 2762 days 08:52:33.436868
 2723 days 08:52:33.436868
 1666 days 08:52:33.436868
 1627 days 08:52:33.436868
(4 rows)

You can also subtract numeric value from the date. This subtracts number of days from a specific date. The following query subtracts 7 days from the date_of_join field value.

dbase=# select date_of_join – 7 as output from employee;
(4 rows)

3. Round the interval (above difference) to the nearest day using date_part()

Use the following query to round the number of days to the nearest day.

dbase=# select date_part('days', now() - date_of_join) as days from employee;
(4 rows)

4. Breakdown the date interval into number of years, months and days using age()

There is the another way to find the interval between the current date and date_of_join as shown below.

dbase=# select age(date_of_join) from employee;
 7 years 6 mons 23 days
 7 years 5 mons 15 days
 4 years 6 mons 23 days
 4 years 5 mons 15 days
(4 rows)

5. Retrieve any sub-fields from the Timestamp using PostgreSQL extract()

Postgres date functions allows you to extract the specific sub-field form the date. Following query extracts the year from date_of_join field.

dbase=# select extract(year from date_of_join) as output from employee;
(4 rows)

6. Truncate a particular date field using PostgreSQL date_trunc()

Postgres provides the facility to truncate the date to specific precision. The following query gives you start date of the month based on the value in the date_of_join field.

dbase=# select date_trunc('month',date_of_join) as output from employee ;
 2002-11-01 00:00:00-08
 2003-01-01 00:00:00-08
 2005-11-01 00:00:00-08
 2006-01-01 00:00:00-08
(4 rows)

7. Display Postgresql Date in Various Format using to_char()

The following query displays the date in “dd/mm/yy” format.

dbase=# select to_char(date_of_join,'mm/dd/yy') as output from employee;
(4 rows)

The month and day of date_of_join field can be displayed as shown below.

dbase=# select to_char(date_of_join, 'FMMonth FMDDth') as output from employee;
 November 23rd
 January 1st
 November 23rd
 January 1st
(4 rows)

Display the full abbreviation of day and month as shown below.

dbase=# select to_char(startdate, 'Dy (Day), Mon (Month)') as output from employee;
 Sat (Saturday ), Nov (November )
 Wed (Wednesday), Jan (January  )
 Wed (Wednesday), Nov (November )
 Sun (Sunday   ), Jan (January  )
(4 rows)

8. Convert String to Date using PostgreSQL to_timestamp()

Postgres provides the way to convert a string value into proper date format as shown below.

dbase=# select to_timestamp('201024June10:12am', 'YYYYDDFMMonthHH12:MIam') as valid_time;
 2010-06-24 10:12:00-07
(1 row)

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{ 6 comments… add one }

  • Tanmay Joshi July 9, 2010, 6:32 am

    Nice refresh :)

  • Ali Naser June 30, 2011, 7:55 am

    I have two times like starttime = 07:40 AM and endtime = 11:05 AM as string/text field
    I want to check a time suppose 08:40 AM is between starttime and endtime is true or false

  • Rick August 27, 2011, 9:01 am

    Hi Ali,


    Select ’08:40′::time BETWEEN ’07:40′::time AND ’11:05′::time

    that’s all…

  • birju August 29, 2011, 8:04 am

    thanks..thanks a lot

  • Celso Soares September 20, 2011, 7:41 pm

    that complex solution worked for me:

    now()::time BETWEEN to_timestamp(ps.contact_period_since || ”, ‘HH24′)::time AND to_timestamp(ps.contact_period_until || ”, ‘HH24′)::time

  • Alastair November 25, 2013, 2:21 pm

    Hi, I am looking to extract the number of completed months between a date in a table and todays date so that it can be used in another formula. I created a view (select age(date_in_table) from table;) but it shows years, months and days. Do you know how I would do this?


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