There is an application with search input that gives an opportunity to search for contacts by their information stored in database. For example, I can type 0972133122 Alan and my search engine must return all contacts whose firstname is Alan & whose numbers match 0972133122 string. Of course, I can just t…
Tag: node.js
Sequelize – is it possible to limit the number of record in junction table
There are 3 tables student_teacher, student, teacher with below relationship. Each teacher will be responsible for 5 students, so the relationship should be 1 to Many, but I decide to create a junction table for storing extra information for this relationship. When I create a student_teacher record, the paylo…
How to condense returned rows of users with multiple roles
I’m trying to wrap my head around this logic, but simply having a tough time. While trying to keep the database normalized, users can have multiple roles (example shows 2, but could have more than 2, currently have 6 total roles), and I’d like to return data to make it easily viewed on a front end UI. Tables …
InfluxDB placeholder “Empty bound parameter”
I’m struggling to format a InfluxDB query using placeholders. Here I query with multiple placeholders. The values are defined in the placeholders object, as seen below, Once sent, an error 400 – error parsing query: empty bound parameter In the error I can see the GET request, where it appears tha…
Express-Postgres fails to apply array filter: error: operator does not exist: integer[] && text[]
The same query works on the terminal. But for some reason I’m getting an error: pg.query is unable to process the expression path && Array[$1] using this: https://www.postgresql.org/docs/9.2/functions-array.html Answer This should work: Why? Short answer: type resolution. Long answer: Concluding…
Converting sql data to json but json file include recordset
I’m trying to convert sql data to json data but when file is completed I get something ‘recordset’ what is this and how do i get rid of it. —–This is how I am getting the json .— Please tell me how i get rid of recordset, square brackets and output and rowsafftectd Answer W…
SQLite table is only able to hold 1 row?
So, I have 2 tables, that I’ve added per the documentation, but something weird happens whenever I try to add a row to them. The data is written into the .db file, but whenever I query it, it only returns the first row. I can still update, and read these rows normally, but any data I write to them, just
How to show multiple tables list in MySql
How to show multiple table list in mysql I have a query that has two tables one for patients and the second one for patients who has tested for covid-19 I want to show all the patients either they tested or not If tested then show the result with his/her name It only showing the patients who has tested for
Displaying Multiple Rows of Data from Two Tables with a One to Many Relationship
I have two tables. Tracks and metadata. Tracks can have multiple metadata attributes, but metadata can only be attached to a single track. The metadata table has a foreign key for a track ID, but the tracks table has no foreign keys for metadata. I am trying to find the best way to get this result: Essentiall…
PostgreSQL: deadlock without a transaction
I have a route (in a node JS app) that inserts and updates some data in a PostgreSQL database (version 13). In pseudo-code, here are all queries that are done in sequential order: On some instances of the app without that much traffic that writes on their own table, I have many deadlocks. I don’t unders…