I am using using MySQL (InnoDB engine). I am running SQL query with WHERE IN statement which is also ordered. I decided to create the perfect index, so my query will not run slow. Surprisingly, after creating the perfect index…
I'm working on a project with a MySQL database. I have some CTEs that summarize features of the users (each CTE summarizes one feature). Then I have a last query that joins all other CTEs on a column named user_id.…
Consider an example table of items with three columns: id (UUID, primary key) time (TIMESTAMPTZ) store_id (UUID, foreign key) There is a covering B-tree index on (store_id, time) INCLUDING (id). Finding the top-N items I'd like to write a query…
I am developing a chatting application. I have written a SQL to get the active chats associated with the user. It used to get user to user chat and group chats based on sort it in descending order based on…
Postgres behaves radically differently on parameters that don't change the result. -- This query is fast (~ 40 ms) WITH filtered_scans AS ( SELECT id FROM scans WHERE scans."createdAt" BETWEEN NOW() - INTERVAL '26 day' AND NOW() AND scans."applicationId" =…
id Plot_name Measurement firmware_revision 1 InboundTraffic1Byte 300 1.5 2 InboundTraffic500Bytes 200 1.5 3 InboundTraffic1000Bytes 100 1.5 4 InboundTraffic1Byte 1.6 5 InboundTraffic500Bytes 200 1.6 6 InboundTraffic1000Bytes 100 1.6 A MySQL database stores measurements from performance tests, and there is a Grafana…
minimize sum(j in tavail) 0.2*(ptn[j]*1000000-pln[j]1000000+sum(k in nport)pevch[j][k]- sum(k in nport)(DOD1[k][j]-dod[k][j])cap[k][j]1000) +0.8(sum(j in tavail)(-sum(k in nport)(-32768DOD1[k][j]+49546)(DOD1[k][j]-dod[k][j])*cap[k][j]*1000); This is the mentioned objective function. Here the weight taken is 0.2 and 0.8. With change in weightage values only objective function value is changing.…
I have to retrieve a list of postings, by one or more category IDs. I do not want to have duplicate postings in my results. I'm only interested in responses that directly relate, or can draw relations with MySQL 8…
I've noticed that full text searches in MySQL do not seem to speed up when reducing the search pool with additional where clauses or joins. For example: SELECT * FROM `blog_posts` WHERE `id` = 1 AND MATCH (post_body) AGAINST ('+mango…
here i need an help like how to optimize this union all query the table has index for where clause column but it's not picking it up and i even tried with force index none of that works any better…