I've looked around and I can't figure out the right syntax for accessing the month and comparing with the current month. For example, if we want to truncate the date and time value to the nearest hour or week, it is possible to truncate using the date_trunc function. These SQL-standard functions all return values based on the start time of the current transaction:DATE_TRUNC. Only accepted if source is of timestamptz type. First, we have the date part specifier (in our example, 'month'). answered Aug 18, 2015 at 10:52. Teams. The following bug has been logged online: Bug reference: 2664 Logged by: Yoshihisa Nakano Email address: nakano. Let’s group the table’s data by “DAY” via the DATE_TRUNC () function: SELECT DATE_PART ( 'DAY', publish_date) day_of_month, COUNT. Current Date/Time. 9. Postgres has date_trunc which operates on timestamp or interval, and:. This uses PostgreSQL’s date_trunc () function, along with some date arithmetic to return the results we want. field selects to which precision to truncate the time stamp value. id) FROM ( select to_char (date_trunc ('day', (current_date - offs)), 'YYYY-MM-DD') AS date FROM generate_series (0, 365, 1) AS offs ) d JOIN sharer_emailshare se ON (d. In this article I will go over the three date/time related data types, and the two most useful date/time functions…postgresql error: function date_trunc(unknown, text) does not exist LINE 1 #9783. This is the simplest and fastest. date_trunc. Example 2: Truncate a TIMESTAMP value to the beginning of the hour. What I want instead is a function that takes three parameters, so I could do make_date(2000, 1, 2) and use integers instead of strings, and returns a date (not a string). Table 9. It takes 4 bytes of memory to store any date value in PostgreSQL. For formatting functions, refer to Section 9. sql. Its Java equivalent is:Using the connect by trick for generating numbers you can extend that to generate dates and times…. This query is working for me to give me the running total of total IDs by week. SELECT DATE_TRUNC('minute', some_date) FROM some_table; This was working fine but I got to know that index made on some_date column will be futile because indexes doesn't work with DATE_TRUNC(), Index created was as follows :. The functions in this section use a format string that is compatible with JodaTime’s DateTimeFormat pattern format. postgresql error: function date_trunc(unknown, text) does not exist LINE 1: SELECT DATE_TRUNC('day', "Date") AS __timestamp, ^ HINT: No function matches the given name and argument types. ) This function takes two arguments. Note: In PostgreSQL, the EXTRACT() and DATE_TRUNC() functions can also be used to group the table’s data based on a specific year. Closed billy-odera opened this issue May 11, 2020. The quarter of the year (1 - 4) that the date is in SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40'); Result: 1. (2) as CONCAT_WS appears to require text, not numeric input, you may have to do something like mutate (the_year = as. Stack Overflow. timestamp)) from rollup_days as rp; To convert the timestamp back to a bigint, use extract ()Use the date_trunc method to truncate off the day (or whatever else you want, e. Here is my sql below (This is based on Postgres. 3. 6. g. 'QUARTER': truncate to the first date of the quarter. "deleted_at" IS NULL). The following illustrates the syntax of the date_trunc function: date_trunc ('datepart', field) Code language: SQL (Structured Query Language) (sql) date_trunc ( field, source [, time_zone ]) source is a value expression of type timestamp, timestamp with time zone, or interval. The subtraction of timestamps yields an interval. They both do very different things. 26 lists them. GitHub Gist: instantly share code, notes, and snippets. The date function used to truncate a date or datetime value to the start of a given unit of duration. g. 2. source is a value expression of type timestamp or interval. All hours in a day: SELECT TRUNC (SYSDATE) + (LEVEL - 1) / 24 FROM DUAL CONNECT BY LEVEL <= 24. Q&A for work. 33. One possibility: select year * '1 year'::interval + '0000-01-01'::date; I like this way because it avoids conversion between text and integer (once all the constants are parsed). The quarter of the year (1–4) that the date is in. ). A general solution for any time interval can be based on the epoch value and integer division to truncate. To group data by year, you can use the DATE_TRUNC function with ‘year’ as the first argument. DATE 'YYYY- [M]M- [D]D'. ) Details: 'quarter' is not mentioned in the doc as valid fields for date_trunc(). Stack Exchange Network Stack Exchange network consists of 183 Q&A communities including Stack Overflow , the largest, most trusted online community for developers to. g. functions. The PostgreSQL LOCALTIME function returns the current time at which the current transaction starts. For formatting functions, refer to Section 9. DATE_TRUNC is very handy for aggregating your data by a particular date_part, like MONTH. date_trunc(text, timestamp) timestamp: Truncate to specified precision;. Note: All the date field parts other than the targeted. For. You can now use date_trunc (text, timestamp) with Doctrine! Note: You can easily adapt this code for every additional Postgres/MySQL function. Current Date/Time. The DATE_TRUNC () function is used to truncate a date, time, or timestamp to a specified interval, such as the day, week, or month, in PostgreSQL and SQL. Conclusion. That is the query for Q1: select '2020_Q1' as time_frame, id, status, date, agent, country, sale from sales where date >= '2020-01-01' and date < '2020-03-31'Introduction. 9. The quarter of the year (1–4) that the date is in. 摘要：本教程向您展示如何使用 PostgreSQL 的date_trunc()函数，将时间戳或间隔值截断到指定的精度级别。 PostgreSQL date_trunc 函数简介. In the above query within the date_part() function, provided the two values, the unit or the component ‘hour’ and the CURRENT_TIMESTAMP function that returns the current time your system. Based on Fiscal Year system, duration. Share. There is no function you want, but as said in postgresql wiki you can define function for youself: CREATE OR REPLACE FUNCTION round_time_10m (TIMESTAMP WITH TIME ZONE) RETURNS TIMESTAMP WITH TIME ZONE AS $$ SELECT date_trunc ('hour', $1) + INTERVAL '10 min' * ROUND (date_part ('minute', $1) / 10. 30 shows the available functions for date/time value processing, with details appearing in the following subsections. date_trunc will truncate a date or timestamp to the specified date/time part. date_trunc. If you need to, you can have your own in the following ways as a. functions. It may be ugly, but it sure works! Here is my query: SELECT Date, interval (trunc (date_part ('epoch', time)/1800) * 1800) AS HALFHOUR, SUM (Data) FROM Table GROUP BY Date, HALFHOUR; This seems to work great, and I don't see any performance hit either. The output shows that the current system hour from the timestamp value is 14. ) field is an identifier or string that selects what field to. Introduction to the PostgreSQL date_trunc function. 662522'); date_trunc --------------------- 2022-05-16 12:00:00. ) inside sql (. pyspark. g. To generate a series of dates this is the optimal way: SELECT t. These SQL-standard functions all return values based on the start time of the current transaction:4. fujitsu. Pad on the right of a string with a character to a certain length. date, q1. May I make a request that "Quarter" should be treated as a valid Interval (as a synonym for "3 months"), to be consistent with other date functions that allow it, such as date_trunc() and extract() ? #1. ON d_date(date_actual); COMMIT; INSERT INTO d_date: SELECT TO_CHAR(datum, 'yyyymmdd')::INT AS date_dim_id, datum AS date_actual, EXTRACT(EPOCH FROM datum) AS epoch, TO_CHAR(datum, 'fmDDth') AS day_suffix, TO_CHAR(datum, 'TMDay') AS day_name, EXTRACT(ISODOW FROM datum) AS day_of_week, EXTRACT(DAY. ) field selects to which precision to truncate the input value. for example, in postgresql. For example, if we want to truncate the date and time value to the nearest hour or week, it is possible to truncate using the date_trunc function. ). 9. A) Extracting from a TIMESTAMP examples. , ‘year’, ‘quarter’, ‘month’, ‘day’, ‘hour’, ‘minute’, ‘second’, etc. Table 9. It shows a similar result, converting the date to a month and year value, which changes the day to the first of that month. Some details are different for date or timestamptz. SELECT date_trunc ('hour', date1) AS hour_stump , (extract (minute FROM date1)::int / 5) AS min5_slot , count (*) FROM table1 GROUP BY 1, 2 ORDER BY 1, 2; You could GROUP BY two columns: a timestamp truncated to the hour and a 5-minute-slot. Add a comment. time_zone. We are also looking at upgrading to a newer version of Postgres but that is further out. 9. You would need to use to_timestamp () if. Also, I'm leaving out '10:00'. Delaying Execution. com PostgreSQL version: All Operating system: All Description: date_trunc('quarter',. for example 2018-10-15 will be 2018-10-01 and 2018-10-30 also will be 2018-10-01. . Oracle has the trunc function and PostgreSQL / Redshift have the date_trunc function that allows you to truncate a timestamp to a specific unit of measure like year, quarter, month, week, etc. SQL Server: Date truncation for custom time periods like year, quarter, month, etc. 1+) that I've overlooked. g. If you do want to use BETWEEN (which will only work properly if date is defined with the data type date) then you can use: select * from my_table where date between date_trunc ('year', current_date - interval '1 year')::date and date_trunc ('year', current_date)::date - 1. ) Example of grouping sales from orders by month: select SUM(amount) as sales, date_trunc('month', created_at) as date from orders group by. 1. Basically, there are two parameters we. The date is complete (year, month, and day). SELECT id, name, date_trunc('quarter', date) AS date, AVG(rank) AS rank,. You can truncate the current date to its quarter, then remove 1 day from that (and potentially cast back to date): -- You really only need the last column, the other two just show the different steps in the process SELECT DATE_TRUNC ('quarter', CURRENT_DATE) , DATE_TRUNC ('quarter',. 1) below the day precision (first parameter) the time zone offset of the result is always the same as the second parameters' offset. GROUP BY date_trunc('day', datelocal) ORDER BY date_trunc('day', datelocal); A bit more noisy code, but faster (and possibly easier to optimize for the query planner, too). Neither of those expressions will make use of an index on created - you would need to create an expression based index with the expression used. 'quarter' is valid for date_trunc() and extract() SELECT date_trunc ('quarter', now()); date_trunc-----2021-01-01 00:00:00+00 The DATE_PART () function extracts a subfield from a date or time value. 1. , week, month, and year. date_trunc always returns a timestamp, not a date. SELECT TRUNC(datevalue, 'MONTH') FROM datelist; Result: 01/MAR/22. Extracting the quarter date part from a timestamp. The DATE_TRUNC () function in Postgres truncate a date or time value to a specific precision. yosihisa@jp. 切り捨ては抽出とは異なります。例： タイムスタンプを四半期まで切り捨てると、入力タイムスタンプの四半期の最初の日の真夜中に対応するタイムスタンプが返されます。 The PostgreSQL DATE_TRUNC function is used to truncate the date and time values to a specific precision (into a whole value), such as 'year', 'month', 'day', 'hour', 'minute', or 'second', in a string format. ) field selects to which precision to truncate the input value. date 、 time 、または timestamp を指定された精度に切り捨てます。. A date value represents a logical calendar date (year, month, day) independent of time zone. Improve this answer. The function date_trunc is conceptually similar to the trunc function for numbers. 9. date_trunc('hour', interval '2 days 3 hours 40 minutes') 2 days 03:00:00:. 2) and found the date_trunc function extremely useful for easily matching time stamps between certain days/months/etc. For instance, if you add a month to the 31st of January, with add_months,. . Try this one: select to_char (trunc_date,'FMMonth YYYY') from ( select distinct date_trunc ('month', orderdate) as trunc_date from table order by trunc_date desc ). SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40'); Result: 1. 9. They both do very different things. This function can also truncate a number. date_trunc¶ pyspark. It’s possible in Postgres to truncate or round a given timestamp to some given level of precision. The following table lists the behaviors of the basic arithmetic operators −. Here is how I make a standard quarterly score average with default quarter. Then, removing a day will give you the date of the last day of the month of the provided date. Date Dimension for Postgres. ). Truncates a DATE, TIME, or TIMESTAMP to the specified precision. source must be a value expression of type timestamp, time, or interval. g. To see the schema where orafce is installed, use dx orafce. Go forth and write fearless (read-only) SQL!only date_trunc(text,interval) and date_trunc(text,timestamp) are immutable. (Values of type date and time are cast automatically to timestamp or interval, respectively. 9. Getting the first day is easy and can be done with date_trunc. 1) precision The precision argument specifies fractional seconds precision of the second. Previous: DATE_TRUNC function Next:. Follow. LastAccessDate), quarter = DATETRUNC(QUARTER,. A similar functionality provides the Oracle compatible function TRUNC [ATE] (datetime). 5. For example. Description. The snippet provided below shows how to use the DATE_TRUNC () function in Postgres: DATE_TRUNC (dateField, timestamp); Specify the date field, such as year, month, day, etc. PostgreSQL provides a number of functions that return values related to the current date and time. Avg; Sum; Count; Min; Max; The below example shows that we are using an aggregate function. I have the blow query that I'm trying to use in a BI tool. , week, year, day, etc. Follow answered Jun 19, 2013 at 9:23. select cast (date_trunc ('month', current_date) as date) 2013-08-01. g. Nice. ). the Use of the DATE_TRUNC () Function in PostgreSQL. PostgreSQL provides a number of functions that return values related to the current date and time. PostgreSQLのTIMESTAMP型で値を入れた日時データについて、小数点以下の秒数を「切り捨て」して取得する方法を紹介する。 まずは結論から。 以下のとおり、 date_trunc 関数を使うことで小数点以下を「切り捨て」して取得することができる。In the docs I could only find a way to create a date from a string, e. select cast (date_trunc ('month', current_date) as date) 2013-08-01. This is a timestamp with time zone value which refers in fact to 23:59:59 on sunday, but with 2 hours of difference with UTC time, depends on your locale and settings. DATE_FROM_UNIX_DATE. The most frequently used Postgres date functions and business scenarios where they come in handy: Rounding off timestamps with DATE_TRUNC function. For data type TIMESTAMP WITH LOCAL TIME ZONE this function is calculated within. PostgreSQL Date Functions (and 7 Ways to Use Them in Business Analysis). create index on test (date_trunc('month', foo::timestamp )); the problem with foo at time zone 'GMT' is that the expression foo at time zone 'GMT' is not itself immutable. Common culprits are: > > *) CASE expressions > *) COALESCE > *) casts > *) simple tranformational expressions > *) predicate string concatenation *) time/date functions, ie WHERE date_trunc( 'quarter', some_timestamp ) = '2014-1-1' Though, in this case it's probably much better to teach the parser how to turn that into a range expression. WHERE date_survey >= date_trunc('year', now()); Or maybe add EXTRACT('quarter' FROM date_survey) AS start_season to add the quarter number. I am just highlighting the date modification part) ## 6 days interval "date_trunc ('month', created_at) + (date_part ('day', created_at)::int - 1) / 6 * interval '6 day'" ## 10 min interval "date_trunc ('hour', created_at) + date_part ('minute', created_at)::int / 10 * interval '10 min'". , 2000-12-31. Postgres quarter function. Truncation does not remove the month and day; instead it sets them to the earliest date in the specified period. g. . (Expressions of type date are cast to timestamp and can therefore be used as well. Date_selector >) AS ddate, SUM (value1) AS value1FROM `project. SELECT distinct (CASE WHEN {PERIOD} = 'Previous Quarter' AND pto. date_trunc () The return type of the date_trunc function is a timestamp. It can also return a number truncated to the whole number if no precision is defined. RTRIM. The image you added to the question suggests that the function is in pg_catalog, but the extension is. The date_trunc function truncates a TIMESTAMP or an INTERVAL value based on a specified date part e. PostgreSQL DATE_PART () function is mainly used to return the part of the date and time; the date_part function in PostgreSQL will subtract the subfield from the date and time value. Chapter 9. A primer on working with time in Postgres. Oracle's DATE data type (which is what sysdate returns) always contains a time part which can not be removed. parse_datetime(string, format) → timestamp with time zone. 1 Share Follow The DATE_TRUNC () function is used to truncate a date, time, or timestamp to a specified interval, such as the day, week, or month, in PostgreSQL and SQL Server. 0) $$ LANGUAGE sql;The PostgreSQL DATE_TRUNC function is used to truncate the date and time values to a specific precision (into a whole value), such as 'year', 'month', 'day', 'hour', 'minute', or 'second', in a string format. PostgreSQL has several of functions for manipulating the dates such as extracting. dataset. ; part_number (required): Requested part of the split (1-based). The function date_trunc is conceptually similar to the trunc function for numbers. source must be a value expression of type timestamp, time, or interval. A bigint is not "a timestamp", so you must convert the number to a date before you can apply date_trunc () on it: Select date_trunc ('day', to_timestamp (rp. The date_trunc(text, timestamptz) variant seems a bit under-documented, so here are my findings:. 2k 3 64 88. If you pass a DATE value, the function will cast it to a TIMESTAMP value. Almost as it can't take any interval with units of months or more (due to varying duration). It takes a date part (like a decade, year, month, etc. Learn more about Teamsdate_trunc('hour', timestamp '2001-02-16 20:38:40') 2001-02-16 20:00:00: extract. To see the objects provided by the extension, run dx+ orafce. For example: Truncating a timestamp down to the quarter returns the timestamp corresponding to midnight of the first day of the quarter for the input timestamp. 16. ; delimiter_text (required): Text representing the delimiter to split by. date_dim_id INT NOT NULL, date_actual DATE NOT NULL, epoch BIGINT NOT NULL, day_suffix VARCHAR(4) NOT NULL, day_name. Current Date/Time. To have one row per minute, even when there's no data, you'll want to use generate _ series. The easiest thing to do is to pass in dates for the start and end of the month: select * from generate_series ( '2018-08-01' ::timestamptz, '2018-08-31' ::timestamptz, '1 day' ); That works as expected, but it's cumbersome. demo:db<>fiddle. date_trunc () was added in PostgreSQL 7. g. com PostgreSQL version: All Operating system: All Description: date_trunc('quarter',. ) field is an identifier or string that selects what field to. I am trying to use the Date_Trunc for MONTH function in a SQL statement but somehow it is not working for me. The PostgreSQL formatting functions provide a powerful set of tools for converting various data types (date/time, integer, floating point, numeric) to formatted strings and for converting from formatted strings to specific data types. What I need is to "round down" the month to day one, and I. Note that the specifier is a string and needs to be enclosed in quotes. 9. ) field selects to which precision to truncate the input value. To verify that, connect to PostgreSQL with psql and run dx to list the extensions. DATE '2000-01-02'. I came across this query: WITH cost AS (SELECT well_schedules. trunc() will set that to 00:00:00 If you want a date/time value (=timestamp) where the time part is 00:00:00 then you can use current_date::timestamp or date_trunc('day', current_timestamp). 2. 切り捨ては抽出とは異なります。例： タイムスタンプを四半期まで切り捨てると、入力タイムスタンプの四半期の最初の日の真夜中に対応するタイムスタンプが返されます。The PostgreSQL DATE_TRUNC function is used to truncate the date and time values to a specific precision (into a whole value), such as 'year', 'month', 'day', 'hour', 'minute', or 'second', in a string format. The DATE type in PostgreSQL can store a date without an associated time value: PostgreSQL uses 4 bytes to store a date value. for example 2018-10-15 will be 2018-10-01 and 2018-10-30 also will be 2018-10-01. region, q2. Sorted by: 2. and while the condition is > '2018-10-01' then all dates in the month October will not be shown in the result. Ex:If I have 2010-01-01, I would like to return 2010-03-31, and so on. However, date_trunc('day', created) is not equivalent to the other expressions, because it returns a timestamp value, not a date. g. Sorted by: 3. LOCALTIME(precision) Arguments. Finding the last date of the previous quarter from current date in PostgreSQL Ask Question Asked 477 times 0 For example: If my current date is 2022. These SQL-standard functions all return. 789'); date_trunc 2020-04-01 00:00:00date_trunc('hour', timestamp '2001-02-16 20:38:40') 2001-02-16 20:00:00: extract. 9. 1-19ubuntu1) 10. The first removes the hours and smaller units from the timestamp, but still returns a timestamp, while the latter returns the timestamp cast to a date. g. decade. A primer on working with time in Postgres. Sintaksis. New in version 2. sql. First, we have the date part specifier (in our example, 'month'). The date_trunc function truncates a TIMESTAMP or an INTERVAL value based on a specified date part e. 2 Answers. EXTRACT, date_part EXTRACT(field FROM source) The extract function retrieves subfields such as year or hour from date/time values. I am converting a postgres app to an Oracle app. start }}'::timestamp) The result of that is a timestamp from which you can subtract the interval: date_trunc. quarter: Quarter (1 to 4) second: Seconds (and fractional. 3. 1994-10-27. CREATE OR REPLACE FUNCTION round_time (timestamp with time zone) RETURNS timestamp with time zone AS $$ SELECT date_trunc ('hour', $ 1) + interval '5 min' * round (date_part ('minute', $ 1) / 5. 4. Finally, it returns the truncated part with a specific precision level. (Values of type date and time are cast automatically to timestamp or interval, respectively. +01 +02 etc depends on your time locale's daylight saving rules. 1. 注釈. -- date_trunc（日付の切り捨て）の構文 date_trunc( 精度 , 日付・時刻 ); 精度には'year'、'month'、'day'等を指定します。. It's bad practice but you might be forgiven if you use. To get week start and end date (as 0 for Monday and 4 for Friday): select cast (date_trunc ('week', current_date) as date) + 0 || '-->' || cast (date_trunc ('week', current_date) as date) + 4; 2015-08-17-->2015-08-21. source must be a value expression of type timestamp, time, or. (In our example, we used month precision. You can fix a date or remove days from current day. ) field selects to which precision to truncate the input value. 参数 field. 5. Dates are stored using the DATE datatype in the PostgreSQL database. The date_trunc function in redshift is specifically used to truncate the specified precision. You can readily convert them to the format you want, get the difference between two values, and so on. fujitsu. If they went and called their system function DATE_TRUNC or even TRUNC, they might have some object naming issues to contend with. If the contraint should apply to the tservice as type "date" you might as well create the tservice column as type "date" instead. Postgres Pro provides a number of functions that return values related to the current date and time. The time zone. The syntax of the function is as follows: DATE_TRUNC ('precision', expression); where expression is a timestamp or an interval to truncate. Improve this answer. Practical examples would include analyzing company’s quarterly. 2017-05-14 20:38:40. sql. Connect and share knowledge within a single location that is structured and easy to search. EXTRACT, date_part. 1 Answer. WEEK: The number of the week of the year that the day is in. For formatting date/time values for display, see Section 4. This is not by any means an exhaustive guide to date and time expressions in BigQuery. 2 (Ubuntu 13. date 、 time 、または timestamp を指定された精度に切り捨てます。. You would need to use to_timestamp () if you really want. Ordering by month & year numbers in Postgres. 9. We had discussed about the Date/Time data types in the chapter Data Types. You can then add more conditions to the CASE/WHEN for additional quarters. The function “CURRENT_TIMESTAMP” is used with the “SELECT” statement in the above example to get the current date with the timestamp also which is “2023-06-16 10:58:01. string_text (required): Text to be split into parts. DATE_TRUNC() will return an interval or timestamp rather than a number. Working with Dates (SQL) - EXTRACT, DATE_PART, DA…How to truncate date in PostgreSQL? Ask Question Asked 10 years, 2 months ago Modified 10 years, 2 months ago Viewed 42k times 22 I'm trying to select all. Share. Table 9. I found these two procedures that abstract equivalent logic: CREATE OR REPLACE FUNCTION first_of_week(date) returns date AS $$ SELECT ($1::date-(extract('dow' FROM $1::date)*interval '1 day'))::date; $$ LANGUAGE SQL STABLE STRICT; CREATE OR. Share. (Values of type date and time are cast automatically to timestamp or interval, respectively. Since this is a performance-critical part of the query, I'm wondering whether this is the fastest solution, or whether there's some shortcut (compatible with Postgres 8. A function for truncating a time value to a specified unit. These SQL-standard functions all return values based on the start time of the current. You need to remove the concat () as it turns the timstamp into a varchar. 0. Ask Question Asked 10 years, 5 months ago. Also, you need to study the week in snowflake. ). order_date BETWEEN [date_start] AND [date_end] GROUP BY interval. Delaying Execution. Adding date_trunc ('quarter', your_date) to your start date will guarantee you start with the beginning of a quarter. The range of values for date values in PostgreSQL is 4713 BC to 5874897 AD. The range of values for date values in PostgreSQL is 4713 BC to 5874897 AD. EXTRACT, date_part EXTRACT (field FROM source) The extract function retrieves subfields such as year or hour from date/time values. date_trunc函数根据指定的日期部分（例如小时、周或月）截断一个TIMESTAMP或一个INTERVAL值，并以一定精度返回截断的时间戳或间隔值。[email protected]_trunc ('month',current_date) + interval '1 month' - interval '1 day'. Update. 4. Gets the number of intervals between two DATE values. Use the DATE_TRUNC() function if you want to retrieve a date or time with a specific precision from a PostgreSQL database. PostGreSQL : date_trunc() returns timestamp with timezone when used on date. Truncating any date or timestamp to the month level will give you the first of the month containing that date. Current Date/Time. 1. g. I am trying to pull entries which happen after April 1st, 2019. For formatting functions, refer to Section 9. 9. This function helps in manipulating numbers as required. It is only meant as a quick reference to those I use most often. PostgreSQL date_part function will allow retrieving subfields from the date and time value, e. Current Date/Time. The quarter of the year (1 - 4) that the date is in SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40'); Result: 1. 32 shows the available functions for date/time value processing, with details appearing in the following subsections. Example of the possible combinations below: Interval. For data type TIMESTAMP WITH LOCAL TIME ZONE this function is calculated within. Example 1: Truncate a DATE value to the beginning of the month. The function date_trunc is conceptually similar to the trunc function for numbers.