Is there a proper way of triggering an event from my PostgreSQL database upon insert/update on a certain table that sends a notification to a separate HTTP server? For a standard REST API application, we mostly interact with the DB…
I need to add constraint(regex) on DB level so that no one able to enter/edit that particular column with invalid input on already existing table. I'm using Sequelize, Postgres. I tried it using migration but still able to enter invalid…
Looked at some of the other posts asking about the error 'column "column_name" referenced in foreign key constraint does not exist' but none of the answers/situations seem to match exactly: Currently have two migration files: 20210123122225_createReservationsTable.js exports.up = function (knex)…
Write a sql query that prints domain interest and number students who are interested in that domain. +------+----------+----------+ | sno | sub1 | sub2 | +------+----------+----------+ | s1 | ds | networks | | s2 | os | ds |…
This is my table Customer (custid, custName, custAddress, custPhone) My Question is List the pair of customers who share the same phone number. I just created the following table:
I am new to SQL and having a hard time to filter out a table using SQL query. I have a table as below CATEGORY | NAME | UID | LOCATION ------------------------------------------------------------------------ Planning | Test007 | AVnNDZEGp5JaMD | USER Planning…
SELECT u.ID, u.display_name as name, u.user_email as email, u.user_registered as registered, ( select meta_value from wp_usermeta where user_id = u.ID and meta_key = 'mobileno' limit 1 ) as mobileno, ( select meta_value from wp_usermeta where user_id = u.ID and meta_key…
Ok this maybe a silly question to you, but really please... i don't understand: Why is Redis used as an RDBMS cache when an RDBMS also has it's own cache? Both Redis and RDBMS is on the same server, or…
I have read in a couple of places that some databases use bloom filters for finding a match when querying a database. In my example I'm using Postgresql which is one of those databases. My question comes up when talking…
Some of my colleagues and I have started to work on an iPhone application that provides a social buying experience for the user. The goal is to provide the user with extended search capabilities (full text, fuzzy search, based on…