Question : I have a customer_orders table in a schema designed to be shared between multiple companies. Each customer_order has […]
Tag: select
Oracle: guaranteeing unmodified database state with queries?
Question : If the first word of a SQL statement is either WITH or SELECT, is the statement guaranteed not […]
How do I perform a UNION query on a dynamic list of tables?
Question : My database has an unknown amount of tables, named with the same prefix followed by a random string: […]
Select records in one table but not in another, when the second table is not matching on primary key
Question : I have two tables from which I need only the results that appear in one table (list) which […]
Efficient way to get last 10 rows of each group in SQLite, can CTE help?
Question : Consider there is a table of job runs history with the following schema: job_runs ( run_id integer not […]
SELECT TOP in MySQL
Question : How can I do this in MySQL? SELECT TOP 50 PERCENT * FROM table What’s the simplest way […]
New field based on sum field
Question : I’m trying to create a new field based in another (sum field) SELECT sum(price) AS old_price, old_price+100 AS […]
How to optimize this select with join and order-by?
Question : We have two tables: CREATE TABLE `messages` ( `id` int(11) NOT NULL AUTO_INCREMENT, `created` int(10) unsigned DEFAULT ‘0’, […]
Select fields from multiple tables
Question : I want to make a query a little complicated, and I’m not able to do it alone. I […]
How do I check three conditions on a select with one query?
Question : I have a table containing email text for welcoming new users. There is a default email, one that […]