In the Magento 2.0 life cycle, at a determined point, we will have considerable megabytes of data on the MySQL database, including information regarding products, orders, customers, and payments. To improve its performance, Magento uses indexed tables to provide faster lookups.

However, as your Magento 2.0 e-commerce grows, the indexation feature starts to lose performance too.

In order to correct this issue, you can precompile database relationships using the flat table option in Magento. This technique combines EAV relationships for categories and products in one table to increase the speed of queries. To enable this feature, you can follow these instructions:

If you make changes to your catalog, product, or some page that has a relationship with indexers, the Magento system needs to re-index the information to keep the flat table schema working. You can manage the indexers with the Magento command-line tool, as follows:

The reindex command rebuilds all the product, catalog, customer, and stock information. The index feature enables a fast return of data once the system has no need to process any basic data, such as product price, every single time that the user accesses the store.

Did you notice in the preceding system message one issue about Magento cron job? Cron job allows you to automate this task and others to improve your efficiency. Let's take a look at how cron job works.