My resultant out is this using case when in postgres id name amount1 amount2 amount3 1 abc 10 null null 1 abc null 5 null 1 abc null null 40 I want my output as: id name amount1 amount2 amount3…
In documentation I can see ORDER BY expression is usually put at the end of the query, however, in my case, I want to order products by price first and then choose brands, as a result, I would add "…
This question appears to be slightly different from some of the other questions out there dealing with duplicates on a LEFT JOIN. Here's my situation: I have a list of datapoints associated with a meter. The datapoints are contiguous but…
I would like to find out the average time that a client waits on a response from a project manager in a chat conversation. I need to make sure it only calculates the waiting time for the last client message…
I need to compose a MySQL query, which will count the number of email occurrences per each country I have following mysql table (shop_orders) order_id email country 1 [email protected] _it 2 [email protected] _hu 3 [email protected] _de 4 [email protected] _pl 5…
Situation: Imagine some script that, upon completion, inserts the current timestamp and some other data into a MySQL table. It's executed every thirty minutes, sometimes not at all, leaving gaps in the data. Goal: Have a query that fetches all…
I am trying to create an SQL event that updates n rows every 5 minutes in a table where id between 1 and 100. However I would like the query not to repeat the same rows on each update; for…
I have a table that contains a customer_id, the product they purchased, the timestamp of the purchase, and the rank of the purchase order. I want to know if there is a way in SQL to get overall percentages for…
I'm learning blind SQLi from website "portswigger" and play labs there.Unfortunately, i don't understand, how SELECT "a" FROM users LIMIT 1 can return column "a", if there isn't any column, named "a"(may be i don understand something). And why is…
DELIMITER $$ USE `db_sp`$$ DROP FUNCTION IF EXISTS `bil`$$ CREATE DEFINER=`root`@`localhost` FUNCTION `bil`(num INT) RETURNS VARCHAR(7) CHARSET latin1 BEGIN DECLARE result VARCHAR(7); CASE num WHEN num > 0 THEN SET result = "Positive"; WHEN num < 0 THEN SET result…