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Tag: aggregate-functions

How to get the average of a column in MySQL

I’m trying to find a way to calculate the average of a column (as a double/float or decimal). I’ve found the AVG function in MySQL documentation but I can’t get it to work. Currently I’ve got the following code: Now for some reason this does not work. It returns “Unable to cast object of type ‘System.Int64’ to type ‘System.Double’.” The

Access Bare Columns w/ Aggregate Function w/o adding to Group By

I have 2 tables in postgres. users auth0_id email 123-A a@a 123-B b@b 123-C c@c auth0_logs id date user_id client_name abc-1 021-10-16T00:18:41.381Z 123-A example_client abc-2 … 123-A example_client abc-3 … 123-B example_client abc-4 … 123-A example_client abc-5 … 123-B example_client abc-6 … 123-C example_client I am trying to get the last login information (a single row in the auth0_logs table

Obtain Name Column Based on Value

I have a table that calculates the number of associated records that fit a criteria for each parent record. See example below: note – morning, afternoon and evening are only weekdays What I am trying to achieve is to determine which columns have the lowest value and get their column name as such: Here is my current SQL code to

Aggregated row count differences between tables

I have two MySQL tables A and B both with this schema ID entity_id asset asset_type 0 12345 x 1 .. ……… ….. ………. I would like to get an aggregated top 10/50/whatever entity_ids with the largest row count difference between the two tables. I think I could do this manually by just getting the highest row count by entity_id

SQL total for each row combination

Are there any types of aggregate functions that could help calculate the following? If I have the following data, I want the sum total for each duplicated row. The output would provide total number each row occurs: Answer Why not good old group by and count?