But when more work is needed in the same request, it's best to update our objects immediately.This can be done by implementing an event-listener that will pick up on Doctrine 2's is called the database will be updated. We have set up the "people have jobs at companies" case in such a way that we can directly create and remove jobs.In other words, we work directly with the job, not with the person or company it concerns (by adding a job to it).
By separating the database information into a separate file, you can easily keep different versions of the file on each server.
You can also easily store database configuration (or any sensitive information) outside of your project, like inside your Apache configuration, for example.
In order to optimize the Doctrine 2 ORM query we need to use JOIN and add the required entities to the sample.
Here is the optimized repository method code for obtaining a list of posts.
Suppose we now need to update the creation date of all our posts.
Often it is done by getting all the posts from the database (due to Doctrine 2 documentation) and then updating each Doctrine 2 entity separately in a cycle: As a result, we have the following values in the profiler after updating 100 posts: As we can see, as many as 103 queries were directed to the database. This should already alert you and make you think about how to increase Symfony2 website productivity. Since we were updating entities in the cycle, we received a large number of UPDATE queries to the database.
So for example, a user would belong to many groups and those groups would have many users.
But in the real world we usually treat this process a bit differently: We draw up a contract in which we specify the information that's needed, including the person and company it relates to.
I have been trying to write this Doctrine 2 ORM tutorial for a long time but just couldn’t get down to it. So here I’m sharing some techniques for working with Doctrine2 ORM which will help to improve the site performance on Symfony2 (precisely any site that uses Doctrine2 ORM). Let’s say we have 5 authors and their 100 posts and we need to display all the posts with the names of the authors on this page.
I have created a project and put it on a Git Hub as a visual guide so anyone can test my words in action now. Template: But if you look at the profiler (Symfony Profiler Toolbar), you will see this upsetting information: Where did so many queries to the database come from if we made only one request?
One of the most common and challenging tasks for any application involves persisting and reading information to and from a database.