MySQL Tips And Tricks
MySQL is probably the best-known relational database management system. As the ‘M’ of the LAMP web development platform, this open-source solution is hugely popular around the world. Yet its popularity doesn’t mean that everyone who uses it is necessarily getting the most out of MySQL. In fact, it can be a complicated and tricky beast, which even experienced users can struggle to keep running smoothly.
There are various MySQL tips of benefit to beginners and intermediate users of the system. But first, it’s worth taking a moment to remind ourselves what MySQL is – and what it’s for…
Just about managing
A database management system (DBMS) is a software application exclusively focused on managing the data stored in a database. There are a few different types of DBMS, and MySQL is known as a relational DBMS. That means its structure allows users to ID and access data in relation to other pieces of information contained in that database.
MySQL uses Structured Query Language (SQL) to access and manage any database. Based on a client-server model, it works across many platforms. The MySQL server handles all database instructions or commands and is pivotal to the wider system’s operation. A wide range of potential applications includes managing and accessing data from huge commercial databases. It’s also critical in web development, appearing alongside Linux, Apache, and PHP in the LAMP stack used to assemble apps and websites.
MySQL tips and tricks
1. Don’t use MySQL as a queue.
Queues within an application can have a profoundly negative effect on performance, adding latency to the application, and slowing down the server. This is because queues serialize your workload, preventing tasks from being done in parallel. They can also result in a table containing work-in-progress data alongside long-finished jobs.
Key MySQL tips include being careful not to let queues (or queue-like patterns) sneak into your applications. For instance, avoid setting the status of an item so a particular process can claim it before acting on it. A common example is marking an email as unsent, sending it, and then marking it as sent.
2. Quickly retrieve unique data
When managing a huge database, retrieving unique values is a valuable MySQL party piece. You can do this from a single column or multiple columns of your database. It’s a ‘SELECT DISTINCT’ query within MySQL that helps you do so.
Imagine a database called ‘workers’, from which you wanted to see unique names in the column ‘surnames’. Your query would look like this:
SELECT DISTINCT
surnames
FROM
workers
ORDER BY
surnames;
To get unique combinations from more than one column in a database, your query doesn’t have to change much. The following instructions would return unique city and state combinations from a database of customers:
SELECT DISTINCT
state, city
FROM
customers
WHERE
state IS NOT NULL
ORDER BY state, city;
3. Follow the key rules of indexing
It’s easy to get confused about indexes and how a MySQL server uses them. Poorly designed indexes really slow things down, hobbling performance. When you’re designing indexes and queries, remember the three main purposes which indexes serve in a database server:
- Indexes allow the server to find groups of adjacent rows.
- They allow the server to read rows in the desired order, preventing the server from always having to waste time sorting rows.
- Additionally, they allow the server to satisfy entire queries from the index, meaning it doesn’t have to access a full table.
If you keep these purposes in mind, you’ll be able to ensure that indexes and queries are properly designed. This makes executing queries much faster and more efficient.