SQLite: How to limit the number of rows based on the timestamp?

Question

I successfully used the following BEFORE INSERT trigger to limit the number of rows stored in the SQLite database table locations. The database table a

Answer 1

This type of trigger should work fine in conjunction with the other one. The problem appears to be that the SQL is unnecessarily quoting the _id field. It is selecting the literal string "_id" for every row and comparing that to the same literal string.

Removing the quotes around '_id' (both in the DELETE and in the sub-SELECT) should fix the problem.