4/14/2023 0 Comments Redshift current date![]() If the second date or time is earlier than the first date or time, the result is negative. If the second date or time is later than the first date or time, the result is positive. The expressions must both contain the specified date or time part. If you are finding the difference in hours between two timestamps, 8:30:00 and 10:00:00, the result is 2 hours.ĭate|time|timetz|timestamp: A DATE, TIME, TIMETZ, or TIMESTAMP column or expressions that implicitly convert to a DATE, TIME, TIMETZ, or TIMESTAMP. If you are finding the difference in hours between two timestamps, 01-01-2009 8:30:00 and 01-01-2009 10:00:00, the result is 2 hours. In this case, the function returns 1 year despite the fact that these dates are only one day apart. For example, suppose that you're calculating the difference in years between two dates, 12-31-2008 and 01-01-2009. Specifically, DATEDIFF determines the number of date part boundaries that are crossed between two expressions.For more information, see Date parts for date or timestamp functions. Periscope also has a list of common differences between MySQL and Redshift.Checking the docs for Amazon Redshift shows this: DATEDIFF ( datepart, )ĭatepart: The specific part of the date or time value (year, month, or day, hour, minute, second, millisecond, or microsecond) that the function operates on. Calculating difference between 2 datetimes Objective DATE_SUB just reverses the sign.Īnd you'll probably need the Redshift datetime format and MySQL datetime format documentation too. DATE_ADD(NOW(), INTERVAL ‘-1 2’ DAY_HOUR).Note CURRENTDATE returns the start date for the current transaction, not for the start of the current statement. redshift sql currentdate getdate () performance issue Ask Question 1 I would like to know whether using the currentdate or getdate () function on redshift SQL would lower the query performance compared to using '' directly, for example. * Unlike MySQL, if the last argument is a date it will still return a datetime, just with 00:00 hour values Amazon Redshift Database Developer Guide CURRENTDATE function PDF RSS CURRENTDATE returns a date in the current session time zone (UTC by default) in the default format: YYYY-MM-DD. * There's no built-in function for this, but you could look into creating User Defined Functions.Īdd some interval to a datetime value, ie in the future or past. You can use the Redshift date format functions to convert the string literals, integer, date/time etc to required format. You can directly convert the format by specifying the cast operator ( ‘::’) such as ::date, ::time, ::timestamp after the date string literal. TIMESTAMP 'epoch' + 1447430881 * INTERVAL '1 second' Amazon Redshift accepts different date formats, including ISO date time strings. Given a datetime value, extract just the hour / day / minute / etc.Ĭonvert datetime to another timezone ObjectiveĬonvert a datetime value from one timezone to another.ĬONVERT_TIMEZONE(‘UTC’, 'US/Alaska', dttm)Ĭonvert unix timestamp to datetime ObjectiveĬonvert a unix timestamp to a datetime value. The following only work on the leader node and are deprecated, use sysdate or getdate() instead.Įxpressing some datetime value in another format.Įxtracting some date part from datetime Objective Getting current timestamp in session timezone. Getting today's date in session timezone. The default column name for the DATEDIFF function is DATEDIFF. You can name date parts in full or abbreviate them. Setting the current session timezone, so that all subsequent queries will be in your specified timezone. This example assumes that the current date is June 5, 2008. Also we currently use MySQL 5.7.x so if you are already on MySQL 8.x then some of these may be incorrect. Returns a date in the current session time zone (UTC by default) for the start of the current transaction. Note that it's not a comprehensive list, it's just what I use on a daily basis - refer to the MySQL and Redshift documentation if you want more. Summary of date and time functions CURRENTDATE. This is a list of common expressions I use for manipulating date, time, datetime, and timestamp values. My working day involves working mostly with RDS instances running MySQL and a Redshift data warehouse - both use flavours of SQL which are similar but just slightly different enough I keep forgetting syntax differences!
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