MySQL: Using sub-selects to filter results of one table that is not contained in another table

In MySQL, if you have two tables with a shared index and you would like to show the results of one table where the index is not within another table, you can use "NOT IN". Try Googling "MySQL NOT IN" and you get everything but this command, it's almost as if they need to…

MySQL: Exclude ‘group by’ group if field A in any row has value B with “Natural Join”

Querying databases get a little tricky when you have a stack of records associated with another table, perhaps a master table of accounts, and you're trying to filter out values that would exclude the results from another group of results. In this example below, we are getting a list of organization IDs for all countries…