The syntax for DATEDIFF is pretty straightforward: DATEDIFF (datepart, startdate, enddate) Let’s explore the parameters used here: datepart: The unit of time you want to use for the calculation, like year, quarter, month, day, or even smaller units like hour, minute, or second. For SQL Server, if you're sure that the difference is less than 24 hours, you can use timefromparts to get the difference as a time data type. In Oracle, you can simply subtract two dates and get the difference in days. DB : SQL SERVER 2008. Return an integer value representing the specified date part of a specified date. Add a comment |The basic syntax for the DATEDIFF () function is as follows: DATEDIFF(date1, date2) date1: The first date value you want to compare. MYSQL Date diff between multiply dates in the same rows. Try this one: select * from MyTab T where date_add (T. This function returns difference between the given date values in the form of days. Modified 2 years, 2 months ago. Let us take a look at the syntax and examples of the MySQL. expr1 and expr2 are date or date-and-time expressions. This function is used to find the difference between two specified values of date. . 1. The MySQL TIMEDIFF() function returns the difference between two time or datetime values. 1. Besides MySQL DATE, of the database management systems most useful commands is MySQL DATEDIFF. MySQL convert timediff output to day, hour, minute, second format. The MySQL DATEDIFF function returns the difference in days between two date values. This function returns difference between the given date values in the form of days. 45 121 But the actual Date Time Difference should beSimilarly, you can also get only the time part i. orders table as in Example 3, we can use DATEDIFF () to find the interval between today's date and the date on which an order is placed. How to compare two dates ignoring seconds in sql server. I have two dates date column like '2017-12-29' and '2018-01-05' the datediff between these dates is 8, but i want to know the datediff which fall on 2018 which should be 5. hope this helps :) Share. The DATEDIFF function calculates only the date portion, ignoring the time portion in the column. Return the current time. 1 to be 0. DAY_SECOND; DAY_MINUTE; DAY_HOUR; YEAR_MONTH; Technical Details. Again, you. Note: time1 and time2 should be in the same format, and the calculation is time1 - time2. I need, in SQL to convert this result. I've got some code that generates hours between an oldest record in the table (MIN) and getdate (), and am using. Hi All, I have two date Suppose one is getdate() and other one is gatedate() +1 . time_c) FROM users u), (SELECT max. DECLARE @date datetime2 = '2021-01-07 14:36:17. The timestamp difference returns the difference between two dates in seconds. The function counts whole elapsed units based on UTC with a DAY being 86400 seconds. Hi All, I have two date Suppose one is getdate() and other one is gatedate() +1 . Timestamp) WHERE b. Applies to: Databricks SQL Databricks Runtime 10. The quickest method in MySQL if you want to know the time split in to the "hours:mins:secs" hierarchy is to use the TIMEDIFF() function. date2: This is the second date that you want to compare. ) that are available and in this tutorial, we look at how to use the DATEADD function in SQL queries, stored procedures, T-SQL scripts,. For example the following statement produces 99. DATEDIFF () 函数只比较 date1 和 date2 的日期部分。. 0. The output is in hours:min:sec. Instead if i want the value to be returned in. If date1 is earlier than date2, the result will. Applies To. This is alright as DATEDIFF() supports a negative date difference. So if you’re trying to do MySQL datediff seconds, you’ll come to realize that the datediff() function only returns day values. These values can be between 0 and 59. For longer intervals, you can divide by 60 for minutes and another 60 for hours. Getting the number of days between two specified date values where the date is specified in the format of YYYY-MM-DD. 1 Answer. Here is an example that uses date functions. Fisrtly we pass current_timestamp and first date value and return type SECOND as a parameters like : DATEDIFF ('SECOND', DATE '1970-01-01', CURRENT_TIMESTAMP ()) * 1000 the returned result is current_time's millisecond for us. The difference is 25 (hours). SELECT MONTH (GETDATE ()), YEAR (GETDATE ()) 4, 2018. DATEDIFF() also works with date-and-time values, but it ignores the time part. Also note that unlike SQL Server or MySQL, in Oracle you cannot perform a select statement without a from clause. DATE_ADD () Add time values (intervals) to a date value. Second date is the result of now(3) statement. The TIMESTAMPDIFF function returns an estimated number of intervals of the type that is defined by the first argument, based on the difference between two timestamps. 33 sec)Insert some records in the table using insert command −mysql> insert into DemoTa DATETIME if the first argument is a DATETIME value or if the interval value has a time element such as hour, minute, second, etc. 0. Argumen. select dateDiff(current_timeStamp,dob) from sometable 'here dob is the table columnGoal: I want to round to the nearest seconds based on milliseconds < 5##### or milliseconds >= 5#####. The return data type is int. I have a datetime column in my mysql table. It is better if you alias both copies of the table: SELECT w1. TIMESTAMPDIFF ( numeric-expression string-expression. DATE_FORMAT () Format date as specified. For example, in the following statement, the NOW (). The following query selects all rows with a. Learn MySQL Tutorial Reference Learn PHP. As we know that DATEDIFF() function is used to get the difference in a number of days between two dates. The SQL DATEDIFF () is a function, and use to find the difference between two dates. For example, suppose you have values below the start and end times. To count the difference between dates in MySQL, use the DATEDIFF(enddate, startdate) function. starttime and etime = [exceptions2]. Can anyone help to take a look? Thanks! Update: Turns out i forgot to put RETURN DECIMAL(10,2). Yes, because the timestamp handles the leap years. DATEDIFF () returns expr1 – expr2 expressed as a value in days from one date to the other. Use the UNIX_TIMESTAMP function. second, ss, s = Second; millisecond, ms = Millisecond; date1, date2: Required. SQL Server: Round Date Up. 1 Sec = 1000000000 nano seconds. Your answer is the way to go here, almost for certain. Difference between two dates returned in hours,minutes,seconds. The first one use a group by, so MySQL have to calculate the full aggregate before sending all the data. This function can be used when the function results in a number larger than the maximum value that can be stored in an integer data type. The DATEDIFF function is also present in MySQL, but it has a completely different meaning. To define a column that includes a fractional seconds part, use the syntax type_name ( fsp) , where type_name is TIME , DATETIME, or TIMESTAMP, and fsp is the fractional seconds precision. Only the date parts of the values are used in the calculation. Only show hours in MYSQL DATEDIFF. Datediff between hours. Syntax:The DATEDIFF_BIG () function returns a 64-bit bigint data type, that can store values up to 9,223,372,036,854,775,807. First, create and populate sample table (Please save us this step in your future questions):CREATE TABLE face_login_logout (. How to convert Seconds to HH:MM:SS using T-SQL (15 answers) Closed 3 years ago . If start is greater than end the result is negative. It depends on how NULL values are to be interpreted, and the use of the isnull function. SELECT * FROM viewname. What this is doing is taking the current seconds left from the 'end_dt' subtracting 15 and adding it to the 'end_dt', basically giving you 15 seconds left. One month is considered elapsed when the calendar month has increased and the calendar day and time is equal or greater to the start. MySQL timediff function does not give proper output. MySQL - SUM of a group of time differences. SELECT DATEDIFF (month,'2011-03-07' , '2021-06-24'); In this above example, you can find the number of months between the date of starting and ending. Just convert the result in seconds to decimal and to milliseconds and nano sec. Given the two datetimes below, what's the best way to obtain the total duration in hours, minutes and seconds (HH:mm:ss)? Start Time: 2014-03-02 20:55:00. 0. 5. @Enrico - Not true. For example, DATEDIFF(milliseconds, '00:00:00',. The date_diff () function returns the difference between two DateTime objects. date, DATEDIFF(mytable. To accomplish this, we will utilize the rental table, which contains essential information about customer rentals, including the dates they rented and. Flicker is observing that if you have only time information, you can't formally tell how many days are between the events, so your answer can be off by a multiple of 86,400 seconds (the number. 1. datepart Unit di mana DATEDIFF melaporkan perbedaan antara tanggal mulai dan berakhir. MySQL does not natively provide any means of generating all dates (or even integers) within a given interval, so you must either materialise such a table in your application layer, or else store a program within MySQL that generates such a temporary table. 如果 date1 的日期晚于 date2 的日期，它返回一个正数，否则返回一个负数或者 0。. Version: 4. montant / (datediff (NEW. Syntax. DATE () Extract the date part of a date or datetime expression. If, by mistake, you pass the second date value as a value larger than the first, you’ll get a negative value for the date difference. Use this for legacy code (PHP < 5. 9999999', '2006-01-01 00:00:00. Here is. select datediff (second,depart_dt, arrived_dt)/86400 as Day, datediff (second,depart_dt, arrived_dt)/3600%24 as Hour, datediff (second,depart_dt, arrived_dt)/60%60 as Minute, datediff (second,depart_dt, arrived_dt)%60 as Second from yourtable. 9 and 2. 0 Share. The MySQL DATEDIFF() function calculates the number of days between these two dates. Only the date parts of the values are used in the calculation. Below query is my sql server query and I want it to convert it into hive query: select DATEDIFF([minute], '19000101', '2013-01-01 10:10:10') Stack Overflow About1. Let us walk through them quickly: To calculate the difference between dates in days – SELECT DATEDIFF (`DATE-A`, `DATE-B`) FROM `TABLE`. DAY_SECOND; DAY_MINUTE; DAY_HOUR. This makes it suitable for producing day intervals for DATE , DATETIME , or TIMESTAMP values. Return Value of MySQL DATEDIFF() Function To convert a date/datetime expression into seconds, use the function TO_SECONDS. Date Interval Calculation: The number of specified date parts between two provided dates is found using the DATEDIFF () method. String otherwise. MySQL - TIMEDIFF () Function. I need to find the time difference in Hours for the following Dates in MySQL - Can i use Datediff functions? 2014-01-01 07:27:21 and 2014-02-01 11:29:00 I tried using DATEDIFF(MINUTE,'2014-01-01. SELECT * FROM table WHERE TIMESTAMPDIFF (MINUTE,timestamp,NOW ()) AS thisisit. Now it only runs DateAdd () once, and it can use an index (if one exists), to only load the rows that match the predicate criterion. The. DatePart. EDIT - I assumed DateTime type. 11. The range of the result is constrained to that of the TIME data type. 6222691' DECLARE @date2 datetime2 = '2022-01-14 12:32:07. You can just subtract datetimes and it will return the value: select (now () - interval 2 day) - (now () - interval 5 day); The result isn't a datetime (it's some decimal coded date -- 3000000 for three days in this case), but it isn't correct to say consider a datetime and an interval as the same datatype. As shown clearly in the result, because 2016 is the leap year, the difference in days between two dates is 2×365 + 366 = 1096. 103 of the German Basic Law forbid a second trial after an acquittal?YEAR. To do datediff, you have to have 2 date or datetime-values. Solution 1 (difference in days, hours, minutes, or seconds): The result is: Discussion: To calculate the difference between the timestamps in MySQL, use the TIMESTAMPDIFF. 1. DATEDIFF () returns ( expr1 – expr2) expressed as a value in days from one date to the other. date2: The second date value you want to compare. I just downloaded the nuget packages for entity framework 6 (EntityFramework. It works if my beginning date is the first of january and the end date the 31st of December, but does not if it stars somewhere else during the year. The following table lists all the valid datepart values. This function includes only the date parts of the arguments while calculating the difference. DATEDIFF() is a function found in SQL Server and MySQL that calculates and returns the difference between two date values. SQL Query returns a negative number but does not interpret it as a negative number but a positive number. The second parameter of DATEDIFF takes a datetime so your string is implicitly converted to a datetime. Let us walk through them quickly: To calculate the difference between dates in days – SELECT DATEDIFF (`DATE-A`, `DATE-B`) FROM `TABLE`. Here is an example that uses date functions. Shortest solution by @TomFp above, for converting a TIME column into seconds. CONVERT (float, DATEDIFF (ms, StartTime, GETDATE ()) / 1000. You can use UNIX_TIMESTAMP to do the calculation in SELECT query. Show 1 more comment. its a countdown with the current date. DATEDIFF() – Return the difference in days of two date values. Relational databases store information in table cells — in columns that describe aspects of an item and rows which tie together the columns. Yes, because the timestamp handles the leap years. TimeStamp - INTERVAL 3 SECONDS AND b. MySQL's DATEDIFF function just takes two parameters: SELECT orderNumber, DATEDIFF (shippedDate, orderDate) AS day FROM datenumtest; Note the order of the date parameters used, which would return some positive number of days assuming that the shipping date be greater than the order date. If you're using Unix Timestamp (integer), then it would be even easier: select * from MyTab T where UNIX_TIMESTAMP () - T. runTime > 20*60. Description. I need to store also milliseconds. 171 2 3. To get what you want, perhaps you should do the diff in seconds and then divide: select cast (datediff (second, min (start_time), min (complete_time))/60. The syntax goes like this: TIMEDIFF(expr1,expr2) Where expr1 and. This function accepts three parameters − the type of interval to measure (such as year, quarter, month, hour, minute, etc. expr1 and expr2 are date or date-and-time expressions. ADDDATE () MySQL ADDDATE () adds a time value with a date. How to wait for 2 seconds: --Example 1 DECLARE @Delay1 DATETIME SELECT @Delay1 = '1900-01-01 00:00:02. 75: SELECT EXTRACT (EPOCH FROM. Query #1 here should tell you which times are the beginnings of chains by finding which times do not have any times below them but within 3 seconds: SELECT DISTINCT Timestamp FROM Table a LEFT JOIN Table b ON (b. SELECT TIMESTAMPDIFF (MONTH, '2012-05-05', '2012-06-04') -- Outputs. This last DATEDIFF example would display the difference between current system date and '2014-02-14' (current system date is returned by the CURDATE function ). If you divide until day, you are fine (every single day every year has the same amount of seconds). This function includes only the date parts of the arguments while calculating the difference. This is alright as DATEDIFF() supports a negative date difference. 較舊的日期減較新的日期會得到負數：. 000 FirstCall = 2012-02-29 12:12:19. date will be null but I don't have the time to check now. I also tried to use DATEDIFF function, but its implementation is different in all of these databases. There are five data types in MySQL. The datepart value cannot be specified in a variable, nor as a quoted string like 'month'. We can get current time by millisecond with h2 DATEDIFF () function. DATEDIFF function. learn mysql. SELECT DATEADD (month, 1, '20220730'); The below DATEADD will add 1 year to the provided date value, the year changed from 2022 to 2023. For this, these must only be stored as permitted data values. Result is expressed as a time value (and it has the limitations of the time. However I want the output to be. Using DATEDIFF() in MySQL. Share. expr1 and expr2 are date or date-and-time expressions. `e. Take a look at the code below - notice the 1 millisecond difference in the two returned values. The first date is the later and the second is the earlier date (flipping them the other way around will return a negative value). Description. Date DateAdd DateDiff DatePart DateSerial DateValue Day Format Hour Minute Month MonthName Now Second Time TimeSerial TimeValue Weekday WeekdayName Year Other Functions:. You could use the microsecond unit and divide by 1000 - MySQL doesn't appear to support milliseconds. SQL Server DATEDIFF function returns the difference in seconds, minutes, hours, days, weeks, months, quarters and years between 2 datetime values. YEAR: Stores the year information only, either in 2-digit or 4-digit format. 107. One may be a date and another is datetime. TIME_TO_SEC() – Return the number of seconds from a time argument. Stack Overflow MySQL DATEDIFF () returns the number of days between two dates or datetimes. datediff()関数の実行結果の具体例. Viewed 18k times. Where a time stamp is a numerical value representing the number of milliseconds from '1970-01-01 00:00:01' UTC (epoch) to the specified time. 3. To count the difference between dates in MySQL, use the DATEDIFF (enddate, startdate) function. It can be used to do date math as well. How to use datediff function to show day, hour, minute, and second. g. *, TO_SECONDS(a. What does negative one mean when passed as a date in the DATEDIFF function?This implies that the difference between times should not be more then 30 seconds. UNIT can be SECOND MINUTE HOUR DAY WEEK. But I don't understand how to use it to collect differences within the table field. The latter is longer, but in terms of cpu time should be faster. sql. UPDATE MyTable SET NewIntColumn = DATEDIFF (SECOND, '19000101', MyDateTimeColumn) 19000101 is the SQL Server epoch. It supports time series analysis by allowing you to calculate. SubmittedDate = 2012-02-29 07:02:55. The MariaDB DATEDIFF function returns the difference in days between two date values. second uses the hour, minute, and second, but not the fractional seconds. The schema is SYSIBM. Fisrtly we pass current_timestamp and first date value and return type SECOND as a parameters like : DATEDIFF ('SECOND', DATE '1970-01-01', CURRENT_TIMESTAMP ()) * 1000 the returned result is current_time's millisecond for us. Definition and Usage The DATEDIFF () function returns the number of days between two date values. DATEDIFF. DATEDIFF calculates the whole difference between two dates. If you want to check that the difference is less than 1 second, that means that the two dates must be the same, in which case you can simply use the equivalency operator. 0. It can be one of the following formats: Year: year, yyyy, yy As shown by other posters. 25. 0. Follow edited May 23, 2017 at. From the condition in the where clause it appears that you are trying to get data for the same date, however using the datediff for the same day always would result 0. But this returns something like HH:ii:ss. It's a useful function for performing date-based calculations and obtaining insights into the duration between two points in time. . 2. Error] We couldn't fold the expression to the data source. Consider the below query. Possible duplicate of Only show hours in MYSQL DATEDIFF – Sebastian Brosch. SELECT TIMESTAMPDIFF (SECOND, '2010-01-01 10:10:20', '2010-01-01 10:45:59') AS SECONDDIFFERENCE;mysql: convert timediff() to seconds. Consider SQL Server function to calculate the difference between 2 dates in months: SQL Server : -- Difference between Oct 02, 2011 and Jan 01, 2012 in months SELECT DATEDIFF ( month, '2011-10-02', '2012-01-01') ; -- Result: 3. , begin is a DATE value and end is a DATETIME value. hour uses only the hour and disregards all the other parts. 1 Answer Sorted by: 78 Use TIMESTAMPDIFF in MySQL: SELECT TIMESTAMPDIFF (SECOND,from,to);This method returns the difference between two dates formatted as hours:minutes:seconds. This means that multiple references to a function. One practical example of using the DATEDIFF function in SQL Server is in a WHERE clause by selecting all employees in the AdventureWorks2008R2 database whose date of hire was in March 2003. I want the difference to be returned as: 02:45:00 and not only 02:00:00. In MySQL, you can use TIMESTAMPDIFF function. I only put RETURN DECIMAL. `e. SELECT TIMEDIFF ('2007-12-31 10:02:00','2007-12-30 12:01:01'); -- result: 22:00:59, the difference in HH:MM:SS format SELECT TIMESTAMPDIFF (SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00'); -- result: 79259 the difference in seconds. 4 Answers. Here’s the syntax of TIMEDIFF () function: TIMEDIFF (time1, time2); Code language: SQL (Structured Query Language) (sql) In this syntax: time1: The first TIME or DATETIME value. The MySQL DATEDIFF function only considers the date portion of the datetime values, and returns an integer number of days difference. DATEDIFF Function. When analyzing historical data, DATEDIFF () helps quantify. There is MySQL locally, Oracle in production environment and H2 for tests. As documentation states: Only the date parts of the values are used in the calculation. This last DATEDIFF example would display the difference between current system date and '2014-02-14' (current system date is returned by the CURDATE function ). recordDate) = 1 AND w1. learn mysql. MySQL TIMEDIFF () function. Like the. , begin is a DATE value and end is a DATETIME value. When analyzing historical data, DATEDIFF () helps quantify the time. First, a quick example of turning a "number of seconds" into the "hh:mm:ss" format. The returned type of the NOW () function depends on the context where you use it. 0. SELECT DATEDIFF(second, startdate, enddate) as seconds_diff; SELECT DATEDIFF(minute, startdate,. Learn MySQL Tutorial Reference Learn PHP. 1. 0. I'm currently looking for a way to make it ignore the time part. TIMESTAMPDIFF (unit,datetime_expr1,datetime_expr2) Returns. I wrote a query using TIME_TO_SEC function, it worked perfectly, but then the integration tests failed, because there I had H2 instead of MySQL. The problem is that the query is giving only the difference in hours. The timestamp difference returns the difference between two dates in seconds. 更多 MySQL 相關的日期時間函數在這邊. The DATEDIFF() function returns the difference between two dates. To convert a date/datetime expression into seconds, use the function TO_SECONDS. The following statement uses the DATE_ADD() function to add one second to 1999-12. SQL SELECT DATEDIFF (end_time, start_time) as `difference` FROM timeattendance WHERE timeattendance_id = '1484' start_time = 2012-01-01 12:00:00 end_time = 2012-01-02 13:00:00. MariaDB: DATEDIFF Function. I am trying to use Datediff to find out the duration between columnA and columnB. Example. TIMEDIFF () is essential for time-based analysis by enabling you to measure the duration of events or actions. SELECT DATEDIFF ("2020-11-12", "2020-11-19"); MySQL DATEDIFF() With Negative Days Difference. What this is doing is taking the current seconds left from the 'end_dt' subtracting 15 and adding it to the 'end_dt', basically giving you 15 seconds left. You can do. It is not necessary that both the expression are of the same type. An expression that returns a value that is a built-in SMALLINT or. Using the sales. MySQL DATE_ADD function examples. If, by mistake, you pass the second date value as a value larger than the first, you’ll get a negative value for the date difference. But this calculation is done only in one unit at a time. You can use strtotime() to convert two dates to unix time and then calculate the number of seconds between them. You can use the earlier date for the first argument and it will return a negative value. CONVERT (VARCHAR (8),GETDATE (),108) AS HourMinuteSecond. 如果 date1 的日期晚于 date2 的日期，它返回一个正数，否则返回一个负数或者 0。. Temperature; What this query does is join every row of the table with every other row of the same table which has as recordDate the previous day and less. SELECT order_id, required_date, shipped_date, CASE WHEN DATEDIFF (day, required_date, shipped_date) < 0 THEN 'Late' ELSE 'OnTime'. You can then use SEC_TO_TIME (seconds) to get the format hh:mm:ss, and take the right 5 characters if you really need hh:mm. Share. Date DateAdd DateDiff DatePart DateSerial DateValue Day Format Hour Minute Month MonthName Now Second Time TimeSerial TimeValue Weekday WeekdayName Year Other Functions:. Date DateAdd DateDiff DatePart DateSerial DateValue Day Format Hour Minute Month MonthName Now. Share. SQL SELECT DATEDIFF (end_time, start_time) as `difference` FROM timeattendance WHERE timeattendance_id = '1484' start_time = 2012-01-01 12:00:00 end_time = 2012-01-02 13:00:00. SELECT `date_time`,now (),timediff (`date_time`,now ()) FROM `table_datetime`. Quick Example: -- The difference is days between today and yesterday SELECT DATEDIFF (dd, GETDATE () - 1, GETDATE ()); -- Returns: 1 -- The number of seconds in 24 hours SELECT. Note: time1 and time2 should be in the same format, and the calculation is time1 - time2. See Date and Time Data Types and Functions (Transact-SQL) for an overview of all Transact. so if date2 is yesterday and date1 is today it will provide something like this: 00:00:07 I saw the timestampdiff function a couple of times, but I am using MySQL in Domo, and this function is not offered there. MySQL query with DATEDIFF. 0. mysql: convert timediff() to seconds. SELECT TIMEDIFF(NOW(), '2010-11-26 12:00:00'); If you want it as seconds, use the unix timestamp features in MySQL or in PHP, you can convert MySQL dates to PHP quickly using. mysql> SELECT SECOND('10:05:03'); -> 3; SEC_TO_TIME(seconds) Returns the seconds argument, converted to hours, minutes, and seconds, as a TIME value. id` = b. Convert DateDiff into Hours, Minutes, Seconds, Milliseconds Forum – Learn more on SQLServerCentral7. Example Get your own SQL Server. Besides MySQL DATE, of the database management systems most useful commands is MySQL DATEDIFF. I've been busy with this for hours, but I cant get it to work. bash. Returns the time argument, converted to seconds. EXTRACT, or one of: MICROSECOND, SECOND, MINUTE, HOUR, DAY, DAYNAME, DAYOFWEEK, DAYOFYEAR, WEEK, MONTH, MONTHNAME, QUARTER, YEAR. Why does Art. Basically the MySQL DATEDIFF function gives the difference between days between two date values. Below is a MySQL cheat sheet that covers some of the most commonly used commands and queries in. SQL DATEDIFF — Now & Then. The syntax for DATEDIFF is pretty straightforward: DATEDIFF (datepart, startdate, enddate) Let’s explore the parameters used here: datepart: The unit of time you want to use for the calculation, like year, quarter, month, day, or even smaller units like hour, minute, or second. The following example illustrates how to use the. It shows us that there are 36 hours, 15 minutes, and 35 seconds between the two. AI is only as good as the data: Q&A with Satish Jayanthi of Coalesce. If you divide until day, you are fine (every single day every year has the same amount of seconds). SQL 教學. In PostgreSQL, you can take the difference in years, multiply by 12 and add. SELECT DATEDIFF (second, '2019-12-31 23:59:59', '2020-01-01 00:00:00'); A value of 1 is returned because the boundary of seconds is. MySQL interval values are used mainly for date and time calculations. TIME) - TO_SECONDS(b.