Let's assume that we have two tables users and messages with the following fields: users: id, name, email messages: id, content, user_id I want to delete a user but keep all data in messages. Is there a way to do…
I have a SQL query where the list of strings is repeated twice: ('foo', 'bar', 'baz', 'bletch'). What is the most maintainable method to avoid such repetition and make this code more DRY? I am not optimizing query performance, only…
I want to write a Postgres function that looks up the value of a column in a given table. Example setup: CREATE SCHEMA IF NOT EXISTS example; CREATE TABLE example.price_table ( symbol text NOT NULL, time_of timestamptz NOT NULL, price…
Here is my code app.put("/update/:id", (req, res) => { const userID = req.params.id; const sql = "UPDATE quotes SET `first_name` = ?, `last_name` = ?, `company` = ?, `email` = ?, `phone` = ? WHERE id = ?" const values…
I want to write a query which will return records where the due date ( will be calculated from start and end date ) is within next 5 business dayes ( exclude weekends) I tried the following but this is…
Im' quite new to full stack development (coming from UX design). I'm asking in the direction of software design and database query strategies. Quick example: Imagine you have a database with booking for a service including customer info and start…
(sale_id, year) is the primary key (combination of columns with unique values) of this table. product_id is a foreign key (reference column) to Product table. Each row of this table shows a sale on the product product_id in a certain…
I have the following database that I want to use for logging networks: CREATE TABLE ip ( id INT NOT NULL AUTO_INCREMENT, address VARBINARY(16) NOT NULL, -- IPv4 or IPv6 PRIMARY KEY (id), UNIQUE (address) ); CREATE TABLE mac (…
I need your help. I want to create a script to update the flag to 'X' where flag is 'No' and get the first 3 rownum of unique Id. E.g. tablename: TBL_INFO Sample table: ------------------------- ID | FLAG ------------------------- 123…
I'd like to understand why the following 2 queries that select duplicates from the companies table have different execution times. The second query with the JOIN is executed much faster. The query is executed on: a companies table with ~200k…