Here is the syntax of the PostgreSQL date_trunc() function: date_trunc (field TEXT, source TIMESTAMP). Note that the specifier is a string and needs to be enclosed in quotes. Increasing work_mem will speed up the sort though. I have this problem. I want to be able to: apply a mathematical operator to subtract 1 day filter it . 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. 2 Answers. Table 9. Table 9. Conclusion. 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'. The week number will be in the range of 1 to 53, depending on the specific date and the datestyle setting in PostgreSQL. 9. 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. You can create a new b-tree index on an expression, like. - Return Type: TIMESTAMP. source must be a value expression of type timestamp, time, or interval. date dollars 2016-10-03 1 2016-10-05 1 2016-10-10 1 2016-10-17 2 2016-10-24 2I think you need to use a case statement: select (case when @timeinterval = 'day' then date (u. The DATE_PART() function extracts a subfield from a date or time value. 9. 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. 표현범위는 BC. Some details are different for date or timestamptz. All fields that are less than the specified precision are set to 0, or to 1 for day and month. Day: This variable was used with the date_trunc function to convert the date into the day format. Note that truncation is not the same as extraction. The following illustrates the. Date/Time Functions and Operators. These functions all follow a common calling convention: the first argument is the value to be. If you want both quarter and year you can use date_trunc: SELECT date_trunc('quarter', published_date) AS quarter This gives the date rounded to the. 5. and source is the date. Basically, there are two parameters we. SELECT DATE_TRUNC('month', TIMESTAMP '2005-05-21 15:30:30'); Result: 2005-05-01 00;00:00 9. Special calculation is needed for week/quarter. SELECT * FROM generate_series(date_trunc('quarter', '2008-02-01 00:00'), '2009-01-01 12:00', '3 months');. For formatting functions, refer to Section 9. pto_start_date < (date_trunc ('quarter', now () - INTERVAL '1 month') + INTERVAL. Ordering by month & year numbers in Postgres. 1 Answer. 2-1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 10. But, 'quarter' is invalid for interval. 15. 2. if you want timestamp instead of timestamptz cast the date to timestamp first. Share. *, min (date_trunc ('week', date)) over () as first_week from t ) t; Here is a db<>fiddle. Table 9. Sorted by: 89. 9. 1. I'm making my first laravel project, using postgres, and I'd like to be able to access all the people with a birthday this month (my people table has a birthdate field that's a date). A primer on working with time in Postgres. DAY AS datum. Table 9-27 shows the available functions for date/time value processing, with details appearing in the following subsections. The quarter of the year (1–4) that the date is in. Share. 6. Use the DATE_TRUNC() function if you want to retrieve a date or time with a specific precision from a PostgreSQL database. 9. Postgres Pro provides a number of functions that return values related to the current date and time. Assuming you want all "overlapping" time periods, i. 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. order_date) AS interval FROM orders WHERE orders. ). Truncate to specified precision in the specified time zone; see Section 9. order_date BETWEEN [date_start] AND. It can be one of the following and can be used in many combinations. If you pass a DATE value, the function will cast it to a TIMESTAMP value. 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. SELECT * FROM stud_cmp WHERE DATE_TRUNC ('day', start_date) = '2020-01-01' :: timestamp; In the above example, after comparing the start date and with date_trunc functions, it will display the three records which contain the. Get the number of remaining days after excluding date ranges in a table. 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. Try to envision time periods on a straight time line and move them around before your eyes and you will see the necessary conditions. Share. date 、 time 、または timestamp を指定された精度に切り捨てます。. The date_trunc function truncates a TIMESTAMP or an INTERVAL value based on a specified date part e. Both interval and date_trunc have helped me write more effective SQL queries and answer thorny questions about app data. source must be a value expression of type timestamp, time, or interval. The date_trunc function returns a TIMESTAMP or an INTERVAL value. functions. is out of the question as this forces quarters to start on Jan 1st and it has 'hardcoded' quarter starting dates (Apr 1st, Jul 1st, etc). 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. 1. postgresql error: function date_trunc(unknown, text) does not exist LINE 1 #9783. Use date_trunc () to get the start of the quarter and subtract dates: WITH cte (day) AS ( VALUES (date '2021-01-02') , (date '2021-02-05') ,. source must be a value expression of type timestamp, time, or interval. (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。. (Values of type date and time are cast automatically to timestamp or. Syntax: date_trunc(text, timestamp) Return Type: timestamp. The DATE_TRUNC() function in Postgres truncate a date or time value to a specific precision. PostgreSQL에서 DATE_TRUNC () 함수 사용. 2. ) field selects to which precision to truncate the input value. When using this function, do not think in terms of days. 5. In PostgreSQL, DATE_TRUNC () is a built-in date function that truncates/trims the unnecessary part from the date/time. order_date BETWEEN [date_start] AND [date_end] GROUP BY interval. CREATE. //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. Introduction to the PostgreSQL date_trunc function. ) at 2006-10-01 18:55:40 from Tom Lane Browse pgsql-bugs by date From Date. 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. If I use the below query, I get the result as 0. Stack OverflowNotes. date_dim_id INT NOT NULL, date_actual DATE NOT NULL, epoch BIGINT NOT NULL, day_suffix VARCHAR(4) NOT NULL, day_name. g. CREATE FUNCTION end_of_quarter (d date) RETURNS date AS $$ SELECT CAST(date_trunc('quarter', d) + interval '3 months' -. 2. 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. g. interval but not a specific interval like 5 minute or 5 days. (In our example, we used month precision. The problem we’re solving is the need to do group by on time intervals of less than 1 hour. Next. DATE_TRUNC truncates the Postgres timestamp to a specified precision. The DATE_TRUNC() function will truncate timestamp or interval data types to return a timestamp or interval at a specified precision. Here’s a bit of code adapted from the PostgreSQL wiki that I like for creating the ever necessary date dimension in PostgreSQL. The DATE_TRUNC () function is particularly useful for time series analysis to understand how a value changes over time. , hour, week, or month and returns the truncated timestamp or interval with a level of precision. Here's an example: SELECT round (date_trunc ( 'day', your_date_column):: date) AS rounded_date FROM your_table; In this example, replace your_date_column with the actual name of the column that contains the date you want to round, and your_table with the name of the table where the column resides. Column [source] ¶ Returns timestamp truncated to the unit specified by the format. PostgreSQL provides a number of functions that return values related to the current date and time. Functions and Operators. These functions all follow a common calling convention: the first argument is the value. source must be a value expression of type timestamp, time, or interval. SELECT date_trunc('quarter', date - interval '2 month') + interval '2 month' AS quarter , country , device , AVG(rank) AS avg_rank , AVG(score) AS avg_score. Here's the best GROUP BY query I have so far: SELECT d. 1. We have used group by clause with the day. For formatting functions, refer to Section 9. The DATE_PART function can also be very useful. Data warehouse support for the EXTRACT function Google BigQuery, Amazon Redshift, Snowflake, Postgres, and Databricks all support. For formatting functions, refer to Section 9. 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. New in version 2. SELECT TRUNC(datevalue, 'DD') FROM datelist; Result: 26/MAR/22. For example, decade 201 spans from 2000-01-01 to. Manipulating the current date and time 100 XP. fujitsu. 4 shows the mathematical operators that are available for the standard numeric types. Table 9. Example 2: Truncate a TIMESTAMP value to the beginning of the hour. Syntax: date_trunc. start }}'::timestamp) The result of that is a timestamp from which you can subtract the interval: date_trunc. 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. CREATE OR REPLACE FUNCTION last_day(date) RETURNS date AS $$ SELECT (date_trunc('MONTH', $1) + INTERVAL. EXTRACT (field FROM source) The extract function retrieves subfields such as year or hour from date/time values. The date/time functions provide a powerful set of tools for manipulating various date/time types. We are also looking at upgrading to a newer version of Postgres but that is further out. The DATE_TRUNC Function - Amazon Redshift takes timestamp as input and provides a timestamp as output: DATE_TRUNC ('datepart', timestamp) For example: SELECT DATE_TRUNC ('month', '2019-05-07'::timestamp) 2019-05-01 00:00:00. “1st”, “2nd”), WEEK_DAY_DESC (not just “Wed” but “Wednesday”, "Thursday), some keys like. 9. You need to remove the concat () as it turns the timstamp into a varchar. The date_trunc function shortens timestamps so they are easier to read. e. 9. For example. 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. Now that we have seen how to use CAST, EXTRACT, and DATE_TRUNC we can bring together some of the techniques we learned into one practical example. example: SELECT date_trunc ('hour', time 'columnName') from tableName. The date_part function is modeled on the traditional Ingres equivalent to the SQL -function extract: 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. To get sales from the first day of the month, we can use the DATE_TRUNC function. There are other possibilities, but 'day', 'month', and 'year. But the index by field will not be used, you can build a separate index by year and month for this. date_trunc ( text, interval) → interval. Conclusion. Return value. Extracting and transforming date/ time data 50 XP. Table 9. 9. ts BETWEEN a AND b is just a shorthand for writing ts >= a and ts <= b. millennium. date_trunc(text, timestamp) timestamp: 截断成指定的精度； date_trunc('hour. config. source must be a value expression of type timestamp, time, or interval. The date_trunc function contains the two input parameters, i. Or simpler, use the column number: group by 1 (if the expression is the first column in the select clause). この. The Oracle code that I posted returns april 22, so I need postgres to do the same. 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. ) field selects to which precision to truncate the input value. Delaying Execution. 436'); Sample Output:. 9. For example. Select Query SELECT (date_trunc('MONTH', now()) + INTERVAL '1 MONTH -. 31 shows the available functions for date/time value processing, with details appearing in the following subsections. for example, in postgresql. Adding date_trunc('quarter', your_date) to your start date will guarantee you start with the beginning of a quarter. This is used in subquery cal to generate a list of all dates in your data. The following are valid field names. 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. Take a look at AT TIME ZONE described just below date_trunc in the link above, you could use something like. 0. ; delimiter_text (required): Text representing the delimiter to split by. date_trunc('field', source) source is a value expression of type timestamp (values of type date and time are cast automatically). time_zone. Sintaksis. If you want to cast your created_at field, you have to write like this as following: CAST (transactions. 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. Remove the longest string that contains specified characters from the right of the input string. Jimmy. Based on Fiscal Year system, duration. You should be familiar with the background information on date/time data types from. For example: SELECT user_id FROM user_logs WHERE login_date >= '2014-02-01' AND login_date < '2014-03-01'. In PostgreSQL, the date_trunc () function truncates a date/time value to a specified precision. 5874897년이다. Realizing this is an old answer, but I recently ran into this. 5. Connect and share knowledge within a single location that is structured and easy to search. Saved searches Use saved searches to filter your results more quickly date_trunc ( text, timestamp with time zone, text) → timestamp with time zone. yosihisa@jp. 9. In this context, truncation means eliminating an amount of detail in the value represented. 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). ) Details: 'quarter' is not mentioned in the doc as valid fields for date_trunc(). 9. ) and a. select cast (date_trunc ('month', current_date) as date) 2013-08-01. EXTRACT, date_part EXTRACT(field FROM source) The extract function retrieves subfields such as year or hour from date/time values. I have the blow query that I'm trying to use in a BI tool. date_trunc関数. 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. 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. The DATE_PART() function extracts a subfield from a date or time value. ) field is an identifier or string that selects what field to extract. In Postgres, you can use the EXTRACT(), DATE_TRUNC(), and DATE_PART() function to extract the month from a date field and then use the GROUP. AT TIME ZONE. 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. Name of the column: This is defined as the name of the column we used with the date_trunc and to_char functions. Sorted by: 3. 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. Overall, it’s a great function to use to help you aggregate your data into specific date parts while keeping a date format. (Values of type date and time are cast automatically to timestamp or interval, respectively. In other words we can use date_trunc for date values with a cast:. In this case, it is used to truncate the result of the subtraction operation to seconds. 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. たとえば、最も近い分、時間、日、月などに切り捨てることができます。. In this article, we will see how we can store,. I. first day of year + current week * 7 days = closest preceding date with same day of week as the first day of the year. It's not immutable because it depends on the sessions time zone setting. SELECT to_date('2022-05-17', 'YYYY-MM-DD'); to_date ------------ 2022-05-17. SELECT date_trunc. A função DATE_TRUNC do Postgres pode nos ajudar a “truncar” uma data, bem, mas o que isso quer dizer? É simples, ela retorna a data inicial de um intervalo especificado. 8. 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. ). 표현범위는 BC. 5. But almost all SQL databases support these in some form or another. A) Extracting from a TIMESTAMP examples. Date_trunc. Within the Extract keyword we have to mention QUARTER as we are getting quarter from timestamp. source must be a value expression of type timestamp, time, or. (Values of type date and time are cast automatically to timestamp or interval, respectively. The subquery is not strictly needed, but it makes the code easier to read. Severity Only way to work around this right now is to create native queries. select to_char (date_trunc ('month', l. timestamp)) from rollup_days as rp; To convert the timestamp back to a bigint, use extract ()Extracting Dates using DATE_TRUNC Function; Extracting Dates using DATE_PART Function; Combining Functions for Advanced Extraction; Conclusion; Introduction: W hen working with PostgreSQL timestamp data types, it can be challenging to extract specific pieces of information, such as dates. This PostgreSQL tutorial explains how to use the PostgreSQL date_part function with syntax and examples. The return value is of type timestamp with all fields that are less than. PostgreSQL provides a number of functions that return values related to the current date and time. The range of values for date values in PostgreSQL. Use the function date_trunc() instead,. The function date_trunc is conceptually similar to the trunc function for numbers. 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. date 、 time 、または timestamp を指定された精度に切り捨てます。. For the date_part and date_trunc functions, arguments can be `year', `month', `day', `hour', `minute', and `second', as well as the more specialized quantities `decade', `century', `millenium', `millisecond', and. ). ) as we did for the EXTRACT code. Postgres では、 DATE_TRUNC () には次の間隔. century. The precision values are a subset of the field identifiers that can be used with the EXTRACT() and DATE_PART() functions. Get the first date of an ISO 8601 year and week. 31 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. 9. Date trunc will convert the data per day wise. The function you need here is date_trunc: select date_trunc ('second', now ()) -- or minute, hour, day, month. Adding a month gives you the first of the following month. This function is most widely used for creating time series and aggregating at a granular level. Create the column which extracts quarter from timestamp column. My current work around is to map date_trunc as a function and explicitly call it but it seems odd to have to do that. 9. Thanks, -Lars On Thu, 20 Jul 2000, Tom Lane wrote: > Lars <>. Because I have a table that contains time without time zone. 24')); Result: 2017-02-14 20:00:00. One of these functions is DATE_TRUNC. For formatting date/time values for display, see Section 4. 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. It allows us to store and display date and time values with a specific offset from UTC (Coordinated Universal Time). 'quarter' is valid for date_trunc() and extract() SELECT date_trunc ('quarter', now()); date_trunc-----2021-01-01 00:00:00+00 To generate a series of dates this is the optimal way: SELECT t. DATE_PART. In order to ignore seconds, you can use date_trunc () function. This example shows how to use the PostgreSQL to_date () function to convert a specified time string to a date value according to the specified format. Oracle, of course, just. create table test (start date ,"end" date); insert into test values ('2019-05-05','2019-05-10') , ('2019-05-25','2019-06-10') , ('2019-07-05','2019-07-10') ; I am looking for the following output, where for every date between the start and end the person is available only. ) field is an identifier or string that selects what field to. PostgreSQL provides the extract function to get a date's year and week number according to the ISO 8601 standard, which has the first week of every year containing January 4th. ) field is an identifier or string that selects what field to extract. Sorted by: 0. Current Date/Time. You can also add the full timezone name as a third argument. g. : Postgres Professional Home > mailing lists Thread: timestamp date_trunc ('quarter',. What could be going wrong here. 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. 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. , year, month, week from a date or time value. ) Details: 'quarter' is not mentioned in the doc as valid fields for date_trunc(). EXTRACT, date_part EXTRACT (field FROM source) The extract function retrieves subfields such as year or hour from date/time values. Delaying Execution. In Postgres, DATE_TRUNC () has the following intervals. - The value for the “field” argument must be valid. For. Syntax. Postgres has lots of functions for interval and overlap so you can look at data that intersects. 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). SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40'); Result: 1. Table 9. These SQL-standard functions all return values based on the start time of the current transaction:9. Improve this answer. A time zone in PostgreSQL is a region that follows a specific set of rules for handling time. 1. 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. 20 July 2000, 05:00:19. e, quarter one is composed of January, February, and. The query below shows sample data of your user adding an other user with a session over two days (to demonstrate the principle) The subquery day_cnt calculates the minimal start date of the sessions and the count_days that is covered with the sessions. 9. The date_trunc(text, timestamptz) variant seems a bit under-documented, so here are my findings:. INTERVAL allows either YEAR and MONTH to be mixed together or DAY, HOUR, MINUTE and SECOND. SELECT ID, Quarter, Value/3 AS "Value", CASE WHEN Quarter = 1 THEN '2020-01-01' WHEN Quarter = 2 THEN '2020-04-01' END AS "Start_Date", CASE WHEN Quarter = 1 THEN '2020-04-01' WHEN. The DATE type in PostgreSQL can store a date without an associated time value: DATE. 5w次，点赞19次，收藏139次。摘要:Oracle有大量的日期函数可供使用,trunc, new_time,months_between,next_day,last_day,add_months,round等函数. Sorted by: 3. 30 illustrates the behaviors of the basic arithmetic operators ( +, *, etc. g. The date_trunc function shortens timestamps so they are easier to read. The field determines which date/time part will be extracted/pulled out from the given source. 26 Recently, I have been getting familiar with PostgreSQL (using 8. Say, you can truncate it to the nearest minute, hour, day, month, etc. PostgreSQL provides a number of functions that return values related to the current date and time. created_at)) day when @timeinterval = 'year' then makedate (year (u. date_trunc. Hide Details. , year, month, day, etc. 1. Table 9. answered Aug 18, 2015 at 10:52. sql. 9. source must be a value expression of type timestamp, time, or interval. format_mask. So, this new function, date_bin, but it takes (almost) any interval as base for truncation. lead_id) as "# New Leads" from leads l where l. I have a table with a date field in timestamp format (ex: 2016-11-01 00:00:00). Do this even for a single day—e. In this article I will go over the three date/time related data types, and the two most useful date/time functions…The GROUP BY clause in Postgres allows us to group the table’s data based on specific column(s), making it easy to analyze and understand relationships and patterns within your data. 1. date; The results:pyspark. Stack Overflow. The trunc () function is used for truncating numbers, not dates. The precision parameter is case-insensitive. 2. 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. We use quarterly queries quite often. You cannot use the date_part of week when using DATE_TRUNC on an INTERVAL. 4. Subtracts a specified time interval from a DATE value. Goal - create a date table, and show what day of the quarter it. 9.