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How to get minimum and maximum for grouped timestamps?
The GROUP BY makes the “binning”, the min (ts) and max (ts) gives you the maximum and minimum values, and the extra function in the outermost SELECT gives the nulls the way you want (and gets rid of the “epoch_start_time_of_interval” that you’re not interested in).
How to count the number of cells between two dates?
The following formula counts the number of dates in A2:A9 that are equal to or greater than the date in E1 and equal to or less than the date in E2: To count the number of cells that contain dates between two dates, you can use the COUNTIFS function:
How to extract the minute from a timestamp?
EXTRACT (minute FROM timestamp) extracts the minute part of the time The expression. After the cast to integer ( ::int ), integer division ( / 10) effectively rounds to 10-minute intervals ( 0 – 5 ). The CASE expression only adds an end_time if more than one rows fall in the same 10-minute interval.
When to use the timestamp identifier in PostgreSQL?
The CASE expression only adds an end_time if more than one rows fall in the same 10-minute interval. I advise not to use the “timestamp” as identifier. It’s a reserved word in standard SQL and base data type in Postgres. If “groups” are defined by gaps of 10 minutes or more between rows of the same hero:
How to find max value from multiple columns?
And not only the maximum or minimum: we can modify the code to find average, sum, etc. from a group of columns of the same data type.
When to use maximum or minimum value in a table?
Sometimes it’s necessary to find the maximum or minimum value from different columns in a table of the same data type. For example we have a table and three of its columns are of DATETIME type: UpdateByApp1Date, UpdateByApp2Date, UpdateByApp3Date.
How to select rows with Min ( timestamp per hour )?
This will give each row a number, starting from 1 for each hour, increasing by timestamp. The result might look like: 2) Then on the main query we select only rows with rn=1, in other words, rows that has lowest timestamp in each hourly partition (1st row after sorted by timestamp in each hour).
How to get the epoch of a timestamp?
You do that by representing timestamps as “number of seconds since a certain date and time”. The ” epoch ” of a timestamp represents the number of seconds elapsed since a certain time and date (1st Jan 1970, 00:00:00). PostgreSQL (and I think, SQL in general) uses “EXTRACT (EPOCH FROM ts)” to get this value.