Returning random rows in a random order from a relational database is a very hard problem. In this article we will see an antipattern, we will discuss why this problem is so hard, and we’ll examine some imperfect solutions.
Read morePaginating the results of an SQL query
One of the trickiest problems in SQL is to query rows in tranches. This is typically needed in a website search, or in a dynamic catalogue where products appear as you scroll down. You want the DBMS to only return …
Read moreMySQL/MariaDB: run less queries! (thanks to performance_schema)
Do you want to improve your application’s and database server’s performance? Remove useless queries. Yes, you probably have them.
Read moreSearching a phone book and copying names
Why developers need to learn the basics of query optimisation. How to make the learning process easy and pleasant.
Read moreMySQL: IS NULL conditions and indexes (→Vettabase)
It is quite common to use an equality condition and an IS NULL condition on the same columns. Unfortunately, this could make queries very slow.
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