Will an index be automatically be updated if I change a function that is used in it. e.g. CREATE OR REPLACE FUNCTION add_test_prefix(input_text VARCHAR) RETURNS VARCHAR AS $$ BEGIN RETURN 'test_' || input_text; END; $$ LANGUAGE plpgsql; then create an…
Im trying to make a simple webpage that shows random quotes. These are in Russian. I also want to show the translation in a separate box. The quotes are being picked at random. How do I link the index of…
I'm using Mysql 8.0.33. I created a composite index with the expression column_name is not null and can't get the index to be used. What am I doing wrong? CREATE TABLE appointments ( id INT AUTO_INCREMENT PRIMARY KEY, user_id INT…
I am trying to make a component in react where there is an image of a body anatomy and on that image there are names and lines pointing to the relating body part and when you click on the name…
I have a MongoDB collection that stores some test submissions. The highlevel schema looks as follows. { "lessonType": "quiz", "userId": "639cb6d9513a420026eddca1" "courseId": "639cb6d9513a420026eddca2", "lessonId": "639cb6d9513a420026eddca3", ...some_more_fields } Now there are two indexes on this collection. first one: { courseId: 1,…
I'm writing a query in MySQL for a Grafana dashboard, but the performance of only this particular query is very poor. This is the query: SELECT br.reading ,CONCAT(ino.project,"_",SUBSTRING_INDEX(br.sensor,"_",-1)) AS new_metric ,ino.vessel ,ADDTIME(DATE('2023-01-01'),-TIMEDIFF(ino.date,br.datetime)) AS norm_date ,br.sensor FROM db.milestones br INNER JOIN…
Say you want to optimize a query in a postgres database like: SELECT DISTINCT ON (first) first, second, third FROM my_table WHERE second > 100 AND fourth = 3 ORDER BY first, second DESC, third DESC (EDIT: In this example,…
Context: I've been creating a database for a class assignment, the assignment doesn't have detailed instructions, instead gives us a narrative in order to have us make our own assumptions and interpretations as to what to create for the database.…
I am quite new with Redis and cache memory and I am bit confused when searching on the official documentation and previous stackoverflow responses . My use case is very simple : I have to use redis to store a…
If I have two queries with the same field but different sort fields then, do I need to create a single compound index or multiple compound index with different sort fields? I am working on an e-commerce site, where I…