#Redshift current date how to#

Mode walks you through the reasoning behind the query, what each portion accomplishes, how you can tweak it to suit your needs, and the kinds of further analysis you can add on top of it. Here’s the query to make it happen, but read Mode Analytics’ blog post for more information. To define sessions with raw SQL, a great query and explanation comes from Mode Analytics. Segment recommends checking out Looker’s approach here.

With Looker, for example, you can take advantage of their persistent derived tables and LookML modeling language to layer sessionization on top of your Segment SQL data.

#Redshift current date how to#

How to define user sessions using SQLĮach of Segment’s SQL partners allow you to define sessions based on your specific business needs. Segment leaves session interpretation to SQL partners, which let you design how you measure sessions based on how customers use your product.įor more on why Segment doesn’t collect session data at the API level, check out a blog post here. And since Segment’s API is about collecting raw, factual data, there’s no API for collecting sessions. They’re stories Segment builds around the data to understand how customers actually use the product in their day-to-day lives. Sessions aren’t fundamental facts about the user experience. Segment’s API does not impose any restrictions on your data with regard to user sessions. That query returns a table like this: date tracks where event = 'completed_order' group by date Periscope also has a list of common differences between MySQL and Redshift.Select date ( sent_at ) as date, sum ( case when item = 'shirt' then 1 else 0 end ) as shirts, sum ( case when item = 'pants' then 1 else 0 end ) as pants from initech. 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).

* Unlike MySQL, if the last argument is a date it will still return a datetime, just with 00:00 hour values * 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. 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. Setting the current session timezone, so that all subsequent queries will be in your specified timezone. Also we currently use MySQL 5.7.x so if you are already on MySQL 8.x then some of these may be incorrect. 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. 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!