If I use the below query, I get the result as 0. For formatting functions, refer to Section 9. Sorted by: 4. PostgreSQL Version: 9. The TRUNC () function trims the fractional part. The syntax of the function is as follows: DATE_TRUNC ('precision', expression); where expression is a timestamp or an interval to truncate. I have an sql query am trying to make to my postgres db. date_trunc関数. Next. I have a table with a date field in timestamp format (ex: 2016-11-01 00:00:00). sql. functions. Date_trunc (field (month, day, year) from timestamp) ExampleI am using PostgreSQL 9. The DATE_PART() function extracts a subfield from a date or time value. These SQL-standard functions all return values based on the start time of the current transaction:The syntax for the to_date function in PostgreSQL is: to_date( string1, format_mask ) Parameters or Arguments string1 The string that will be converted to a date. performance. 9. 31 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. But there is also no point in casting date literals to date as input parameter. You also have some fiscal year columns that we don’t. (Values of type date and time are cast automatically to timestamp or interval, respectively. Share. first day of year + current week * 7 days = closest preceding date with same day of week as the first day of the year. 9. 6. The return type of the date_trunc function is a timestamp. SELECT date_trunc('month',"BDATE") MTH, COUNT("CUSTOMER_REQUEST_ID") DELIVERIES FROM orders GROUP BY MTHSyntax: add_months(date, integer). Table 9. //每30分钟 select date_trunc('quarter',now()) + interval '15 d 15 h 15 minute 30 second'; //本季度的第15天,15小时 15分 30秒 select date_trunc('quarter',now() ) - interval '1 h'; //每个季度最后一天的晚上11点 select date_trunc('quarter',now. 9. The trunc () function is used for truncating numbers, not dates. These SQL-standard functions all return. Use the date_trunc () function to get the first day of the quarter and then subtract one day. If I use the date_trunc() function, I can aggregate data at an hourly, monthly, daily, weekly, etc. date_dim_id INT NOT NULL, date_actual DATE NOT NULL, epoch BIGINT NOT NULL, day_suffix VARCHAR(4) NOT NULL, day_name. This example uses TRUNC to show the date value as an IW format (which is the week. 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. 9. This list of the. I have tried using something like: date_trunc | 2020-07-01 03:00:00+10 date_trunc | 2020-07-01 02:00:00+10 The local timezone when I ran these examples was Australia/Brisbane. But in the check constraints, I see that the truncated date is being shifted. 24×7×365 Technical Support Migration to PostgreSQL High Availability Deployment Database Audit Remote DBA for PostgreSQL Products Postgres Pro Enterprise Postgres Pro Standard Cloud Solutions Postgres Extensions2) source The source is a value of type TIMESTAMP or INTERVAL. date_trunc¶. 9. Interprets an INT64 expression as the number of days since 1970-01-01. 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. sql. 9. Table 9. source is a value expression that evaluates to type timestamp or interval. Finding events relative to the present time with NOW () and CURRENT_DATE functions. INTERVAL '1-2' YEAR TO MONTH. 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. 2. I need to query for a date like the one in my code, and in postgreSQL i found date_trunc to "cut off" unnecessary information from the date. This is one way to go about it. create index mytable_ts_day on mytable (extract (day from ts)) and this index then can be used for a matching expression like extract (day from ts) = 9, or any other operator on. source must be a value expression of type timestamp, time, or interval. In other words we can use date_trunc for date values with a cast:. 3. so you can distinct it first in the table then do the count. the Use of the DATE_TRUNC () Function in PostgreSQL. Take a look at AT TIME ZONE described just below date_trunc in the link above, you could use something like. ) field selects to which precision to. The extract function retrieves subfields such as year or hour from date/time values. Re: BUG #2664: date_trunc('quarter',. ). 32 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. g. ) Details: 'quarter' is not mentioned in the doc as valid fields for date_trunc(). - The value for the field. Example: PostgreSQL DATE_TRUNC() function : Example: Code: SELECT date_trunc('hour', timestamp. ) field selects to which precision to truncate the input value. ). The following bug has been logged online: Bug reference: 2664 Logged by: Yoshihisa Nakano Email address: nakano. The LOCALTIME function takes one optional argument:. Postgres では、 DATE_TRUNC () には次の間隔. Column [source] ¶ Returns timestamp truncated to the unit specified by the format. It's best explained by example: date_trunc('hour',TIMESTAMP '2001-02. 这是 PostgreSQL date_trunc() 函数的语法： date_trunc ( field TEXT , source TIMESTAMP ) -> TIMESTAMP date_trunc ( field TEXT , source TIMESTAMPTZ , time_zone TEXT ) -> TIMESTAMPTZ date_trunc ( field TEXT , source INTERVAL ) -> INTERVAL SELECT DATE_TRUNC('quarter', TIMESTAMP '20200430 04:05:06. Everything to the “right” of the datepart you selected will be “blank” or go back to the beginning (in other words, if you truncate your query at year, then the month, day and time will “reset” to 01-01 00:00). Table 9. Say,. Saved searches Use saved searches to filter your results more quicklyPostgresql SQL GROUP BY time interval with arbitrary accuracy (down to milli seconds) I want to aggregate data at 5 minute intervals in PostgreSQL. To store date values, you use the PostgreSQL DATE data type. 1 Answer. 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. SELECT date_trunc. WW truncates date to the nearest previous day same to the first day of week of the year. Sorted by: 0. So using date_trunc ('week',now ())-'1 s'::interval; on the right side of your date operator should work. The precision is used to set the number of digits in the fractional seconds precision in the second field of the returned query. g. If they went and called their system function DATE_TRUNC or even TRUNC, they might have some object naming issues to contend with. 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. In order to group our orders by month, in PostgreSQL we'll use the date_trunc built-in function. DATE_TRUNC() will return an interval or timestamp rather than a number. ) Example of grouping sales from orders by month: select SUM(amount) as sales, date_trunc('month', created_at) as date from orders group by. date_trunc () is a system function for truncating a timestamp or interval to a specified unit. g. and source is the date. Delaying Execution. 8. 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. I am trying to use the Date_Trunc for MONTH function in a SQL statement but somehow it is not working for me. Extracting the quarter date part from a timestamp. 3 Answers. 2. SELECT * FROM Conference WHERE date_start >= date_trunc ('month', current_date - interval '1' month) and date_start <. Truncates a DATE, TIME, or TIMESTAMP to the specified precision. date_trunc ( field, source [, time_zone ]) source is a value expression of type timestamp, timestamp with time zone, or interval. Stack Overflow. ) field is an identifier or string that selects what field to extract. 2020-04-01, and has the advantage that subsequent steps in the pipeline can read it like a normal date. Date/Time Functions. Get the first date of an ISO 8601 year and week. You can round off a timestamp to one of these units of time: microsecond. Responses. Optional. Overall, it’s a great function to use to help you aggregate your data into specific date parts while keeping a date format. ) timestamp date_trunc ('quarter',. date_trunc¶ pyspark. g. PostgreSQL - DATE/TIME Functions and Operators. However, with Postgres 14, the EXTRACT function now returns a numeric type instead of an 8-byte float. The week number will be in the range of 1 to 53, depending on the specific date and the datestyle setting in PostgreSQL. 4. The query will return a result with a single column labeled “uptime” that represents the duration of the PostgreSQL database server’s uptime. Postgres quarter function. If you had a date and you wanted to truncate it to the hour, you could use: date_trunc ('hour', date) If you wanted to truncate to the day, you could use this:I am wondering if it's possible to truncate dates other than using the default choices using date_trunc. EXTRACT, date_part EXTRACT(field FROM source) The extract function retrieves subfields such as year or hour from date/time values. You can fix a date or remove days from current day. day::date FROM generate_series (timestamp '2004-03-07' , timestamp '2004-08-16' , interval '1 day') AS t (day); Additional date_trunc () is not needed. 1+) that I've overlooked. Say, you can truncate it to the nearest minute, hour, day, month, etc. For data type TIMESTAMP WITH LOCAL TIME ZONE this function is calculated within. 1. Summary: this tutorial shows you how to use the PostgreSQL date_trunc() function to truncate a timestamp or interval to a specified level of precision. 8. Finally, it returns the truncated part with a specific precision level. -- 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 function timestamp truncated to a specific precision. Given a From Date, To Date and a Fiscal Year system, I want to get all the split-up duration within the given From & To Date based on the Fiscal Year system. The basic syntax of the DATE_TRUNC function is as shown below: DATE_TRUNC(precision, source); where precision is the precision to which you want to truncate the date or time (e. postgresql error: function date_trunc(unknown, text) does not exist LINE 1 #9783. An alternate method would be to either build a functional index on dt::date or to write it this way (using parameter $1 as a date string): WHERE dt >= $1 AND dt < $1 + interval '1 day'. We use quarterly queries quite often. 표현범위는 BC. 8. It will return the date truncated to month precision, e. date_trunc('field', source) source is a value expression of type timestamp (values of type date and time are cast automatically). And I have set up partition table for every month. 28 shows the available functions for date/time value processing, with details appearing in the following subsections. In Postgresql, to truncate or extract the week of the timestamp value, pass the week as a string to the date_trunc function. 1. Take two easy steps to create date_trunc: Break down the datetime into small parts (Year, Month, Day/Hour, Minute, Second) and extract the parts you need. Use the function date_trunc() instead,. SELECT date_trunc('MONTH', dtCol)::date; But getting the last day is not so straight forward. select * from your_table where extract (YEAR FROM createdAt) = extract (YEAR FROM now ()) and extract (MONTH FROM createdAt) = extract (MONTH FROM now ()) Share. As you don't want to include rows from "this" month, you also need to add a condition for that. To use the EXTRACT() function for PostgreSQL convert DateTime to date operation, we have listed some examples: In PostgreSQL format date, to extract a month from a given timestamp, SELECT EXTRACT(MONTH FROM TIMESTAMP '2022-05-12 18:36:49'); Output: extract ----- 5 (1 row)The date_trunc() function is used to truncate to specified precision. extract() complies with the SQL standard, date_part() is a Postgres specific query. Go forth and write fearless (read-only) SQL!{"payload":{"allShortcutsEnabled":false,"fileTree":{"macros":{"items":[{"name":"_utils","path":"macros/_utils","contentType":"directory"},{"name":"calendar_date. 1. Previous. Jimmy. 9. If you need to, you can have your own in the following ways as a. 4. I. ) field is an identifier or string that selects what field to. Postgres date_trunc quarter with a custom start month. The following are a couple custom functions which allow this configuration. It takes a date part (like a decade, year, month, etc. ) This function takes two arguments. date_trunc¶. or you can create your own. The return value is the same data type as the input value. 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。AT TIME ZONE. Q&A for work. ) Details: 'quarter' is not mentioned in the doc as valid fields for date_trunc(). You cannot use the date_part of week when using DATE_TRUNC on an INTERVAL. ). Try to envision time periods on a straight time line and move them around before your eyes and you will see the necessary conditions. (Values of type date and time are cast automatically to timestamp or interval, respectively. Adding a month gives you the first of the following month. 9. Sintaksis. Here are some of my staple date functions. Conclusion. 所以在此只说明Postgresql 中的TRUNC取断函数. SELECT date_trunc ('quarter', now()); date_trunc-----2021-01-01 00:00:00+00. created_at + interval (1 - day (u. Hey so im trying to query from a database, using Sequelize (Node. In PostgreSQL, DATE_TRUNC Function is used to truncate a timestamp type or interval type with specific and high level of precision. It's bad practice but you might be forgiven if you use. In Postgresql, to truncate or extract the week of the timestamp value, pass the week as a string to the date_trunc function. 1 Answer. 2. Introduction. 8. The date_trunc function contains the two input parameters, i. 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。 AT TIME ZONE. date_trunc() also accepts other values, for instance quarter, year etc. In this article, we will see how we can store,. 0) $$ LANGUAGE sql; I am using PostgreSQL 14. The way to count weeks is to truncate the start and end timestamps to the first day of the week, then subtract days. One of these functions is DATE_TRUNC. source must be a value expression of type timestamp, time, or interval. . if you want timestamp instead of timestamptz cast the date to timestamp first. You. What it does: The Redshift add_months function adds months, specified by integer to a date value. ) field is an identifier or string that selects what field to extract. 31 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. 6. date_trunc(field, source [, time_zone ]) source is a value expression of type timestamp, timestamp with time zone, or interval. values date_trunc ('MONTH', DATE ('2007-02-18')) Result: 2007-02-01 00:00:00. Table 9-28 shows the available functions for date/time value processing, with details appearing in the following subsections. These SQL-standard. These SQL-standard functions all return values based on the start time of the current transaction:9. The Oracle TRUNC() function returns a DATE value truncated to a specified unit. 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. This function truncates a date/time value to a specified precision. This can be generalized to any type of grouping. PostgreSQL date_part function will allow retrieving subfields from the date and time value, e. AT TIME ZONE. date_trunc('month', current_timestamp) gives you the start of "this month" so in March this would be 2021-03-1 as the comparison for the upper limit is done using < it will include everything on the last day of February. Within the Extract keyword we have to mention QUARTER as we are getting quarter from timestamp. PostgreSQL; DATE_TRUNC; Last updated at 2023-04-17 Posted at 2023-04-17. To verify that, connect to PostgreSQL with psql and run dx to list the extensions. 30 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. The DATE type in PostgreSQL can store a date without an associated time value: DATE. Introduction to the PostgreSQL DATE_PART function. The subquery is not strictly needed, but it makes the code easier to read. A primer on working with time in Postgres. Covers all your examples. Some common precisions are year, month, week, day, hour or minute. 28 shows the available functions for date/time value processing, with details appearing in the following subsections. The start should be the first month of the current year, the stop is the current date with an interval of 1 month. To build a new timestamp from the date part of the appointment_date and the time value, just add them: appointment_date::date + appointment_end_time::time. 9. ) field is an identifier or string that selects. 11. sql. Pictorial Presentation of PostgreSQL DATE_TRUNC() function. For example. 1. PostgreSQL provides two very similar functions DATE_PART and EXTRACT with different syntax, but identical (DATE_PART returns a double, which can lead to some loss of precision) behavior. . 4時間に1度実行するバッチを作成していて、4時間の間に更新されたデータを取得したい。 閾値として、0msecちょうどで更新日時を比較したい時にdate_truncを使用したので、その備忘録。. Data warehouse support for the EXTRACT function Google BigQuery, Amazon Redshift, Snowflake, Postgres, and Databricks all support. When dealing with dates, it accepts as a parameter a Template Pattern for Date/Time (see link above) then a timestamp, and returns a timestamp. The full-list is available in the Postgres docs. The range of values for date values in PostgreSQL. On 29/10/2018 16:26, Andreas Karlsson wrote: > On 10/29/2018 04:18 PM, Vik Fearing wrote: >> A use case that I see quite a lot of is needing to do reports and other >> calculations on data per day/hour/etc but in the user's time zone. The precision values are a subset of the field identifiers that can be used with the EXTRACT() and DATE_PART() functions. Be aware of corner case pitfalls with type timestamp (or date ) depending on the current time zone setting (as opposed to timestamptz ). I would like to change the date into month. But the index by field will not be used, you can build a separate index by year and month for this. 9. I’d like to produce the generic quarter end date for a given date. 5. 9. dim_time__month_start_date date NOT NULL, dim_time__week_start_date date NOT NULL, dim_time__quarter_start_date date NOT NULL, dim_time__year_start_date date NOT NULL, The redundant columns wouldn't even help performance of the query at hand. Split a string on a specified delimiter and return nth substring. 9. 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. The SELECT statement below extracts the month from the date_renting column of the renting table. Both interval and date_trunc have helped me write more effective SQL queries and answer thorny questions about app data. The corresponding function in PostgreSQL here is date_trunc. pyspark. sql. source must be a value expression of type timestamp, time, or interval. The function you need here is date_trunc: select date_trunc ('second', now ()) -- or minute, hour, day, month. In this case you still need to calculate the start date of the month you need, but that should be straight forward in any number of ways. Explained below with examples: Example 1: Fiscal Year system: Apr to Mar From Date: Jan-05-2008 To Date: May-15-2008. A time zone in PostgreSQL is a region that follows a specific set of rules for handling time. e. (Expressions of type date are cast to timestamp and can therefore be used as well. extract関数の場合は、extract (month from request_time)という書き方だったが、date_trunc関数ではmonthをシングルクォーテーションで囲む必要がある。. created_at as timestamp) at time zone '+08:00'))::DATE AS period_start FROM transactions LIMIT 1. 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. 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. For formatting functions, refer to Section 9. 4713~AD. Here’s an example that returns the last day of the current month: SELECT (date_trunc ('month', now ()) + interval '1 month - 1 day'); Result: 2022-04-30 00:00:00+10. the Use of the DATE_TRUNC() Function in PostgreSQL. –2 Answers. date_trunc ('hour', created) + extract (minute from created)::int / 15 * interval '15' minute. So first the timestamp is converted to a date (that does not have a time), and then the time value is added to that, which yields a timestamp. CURRENT_DATE: DATE: Return the current date: CURRENT_TIME: TIMESTAMPTZ: Return the current time: CURRENT_TIMESTAMP: TIMESTAMPTZ: Return the current date and time with time zone at which the current transaction starts: DATE_PART: DOUBLE PRECISION: Get a field of a timestamp or an interval e. orafce should be among them. 9. 2) at or above day precision, the time zone offset is recalculated, according to the current TimeZone configuration. I think the :: operator is more common in "Postgres land". WHERE date_survey >= date_trunc('year', now()); Or maybe add EXTRACT('quarter' FROM date_survey) AS start_season to add the quarter number. Return value. (Values of type date and time are cast automatically to timestamp or interval, respectively. 文章浏览阅读9. CREATE. Saved searches Use saved searches to filter your results more quickly date_trunc ( text, timestamp with time zone, text) → timestamp with time zone. Fungsi DATE_TRUNC. Special calculation is needed for week/quarter. To see the schema where orafce is installed, use dx orafce. for example 2018-10-15 will be 2018-10-01 and 2018-10-30 also will be 2018-10-01. In the following example, DATE_TRUNC retrieves the beginning of the current month, adds one month to retrieve the beginning of the next month, and then subtracts 1 day to determine the last day of the current month. If so, use date_trunc(): select date_trunc('month', order_date) as yyyymm If you really want a string, you should accept Nick's answer. ). 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. create table foo ( first_of_month date not null check (extract (day from first_of_month) = 1) ); insert into foo (first_of_month) values ('2015-01-01. These queries work fine in oracle but am in the process of converting it to a postgres query but it complains. values date_trunc ('HOUR', TIMESTAMP ('2017-02-14 20:38:40. 9. ) as we did for the EXTRACT code. Share. For example: SELECT user_id FROM user_logs WHERE login_date >= '2014-02-01' AND login_date < '2014-03-01'. The second one which use DATE_TRUNC will tranc any date to the first day of the month. I see that date_trunc function returns timestamp and intervals cannot be cast to date type: select current_date -. PostgreSQL date_part function will allow retrieving subfields from the date and time value, e. 9. The return value is of type timestamp with all fields that are less than. The documentation shows following usage example: SELECT date_trunc('hour', TIMESTAMP '2001-02-16 20:38:40'); Result: 2001-02-16 20:00:00 So I thougt this should work:date_trunc('hour', interval '2 days 3 hours 40 minutes') 2 days 03:00:00: extract. Alternative option. Conclusion. LOCALTIME(precision) Arguments. (Expressions of type date will be cast to timestamp and can therefore be used as well. currently I am coding the exact date for the last quarter, the quarter before and the quarter one year ago. Postgres Pro provides a number of functions that return values related to the current date and time. source must be a value expression of type timestamp, time, or interval. You should be familiar with the background information on date/time data types from. , hour, week, or month and returns the truncated timestamp or interval with a level of precision. I want to generate date data using postgresql function "generate_series" , however I have only advanced as far as the following: SELECT ( DATE_TRUNC( 'month', ld ) + '1 month'::INTERV. config. We have converted date column data. Table 9-26 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. 표현범위는 BC. To generate a series of dates this is the optimal way: SELECT t. SELECT EXTRACT(quarter FROM '2015-01-01'::timestamp) - 1; Result : 0 Chapter 9. Part of AWS Collective. Share. Postgres では、特定のタイムスタンプを特定のレベルの精度に切り詰めたり丸めたりすることができます。. date_trunc () was added in PostgreSQL 7. DATE_DIFF. Required. ) This function takes two arguments. 1. Introduction to the PostgreSQL date_trunc function. 9. First, we have the date part specifier (in our example, 'month'). date_trunc. This is the query: select to_char (calldate,'Day') as Day, date_trunc (calldate) as transdate, Onnet' as destination,ceil (sum (callduration::integer/60. PostgreSQL provides two very similar functions DATE_PART and EXTRACT with different syntax, but identical (DATE_PART returns a double, which can lead to some loss of precision) behavior. Get the last day of the current quarter as a DATE value:I have been trying to simulate the following Oracle statement in PostgreSQL: To reach this, I was already able to simulate the TRUNC () function receiving only one time datatype parameter, which is timestamp without time zone. Table 9. I am using this script to create and populate a partly localized (for Turkish) date dimension table. Sorted by: 2. PostgreSQL provides a number of functions that return values related to the current date and time. - It accepts two arguments, a datePart, and a field. DATE_TRUNC. order_date) AS interval FROM orders WHERE orders. (Values of type date and time are cast automatically to timestamp or interval, respectively. PostgreSQL 13. Assuming you are using Postgres, you need quotes around your date constant and can convert to the right types: WHERE job_date >= DATE_TRUNC('month'::text, '2019. Ex:If I have 2010-01-01, I would like to return 2010-03-31, and so on. 2. The PostgreSQL LOCALTIME function returns the current time at which the current transaction starts. Current Date/Time. 1. I think the shortest and most elegant way to solve this issue is to use date_trunc ('quarter',d) (which will retrieve the start of the quarter) + 3 months - 1 day,. But the week starts on Monday in Postgres by default. (Expressions of type date are cast to timestamp and can therefore be used as well. 5. 5874897년이다. 9. The following example truncates a TIMESTAMP value to hour date part: SELECT DATE_TRUNC('hour', TIMESTAMP '2017-03-17 02:09:30'); Code language: SQL (Structured Query Language) (sql) The following is the output:. We have used group by clause with the day. Julian calendar date (integer days since local midnight on November 24, 4714 BC) Q: quarter: RM: Month in uppercase Roman numerals (I to XII; I is January) rm: Month in lowercase Roman numerals (i to xii; i is January) TZ: Uppercase time zone abbreviation ( to_char supported ) tz: Lowercase time zone abbreviation (only to_char. We are also looking at upgrading to a newer version of Postgres but that is further out. The date_trunc function truncates a TIMESTAMP or an INTERVAL value based on a specified date part e. TRUNC(date, format) Code language: SQL (Structured Query Language) (sql) Arguments. 8. Here’s the current timestamp.