Magento recommends disabling Flat Catalog

[abscom]

I came across this today, which I think needs some community discussion and ideally a firm line from Magento:

https://docs.magento.com/m2/ce/user_guide/catalog/catalog-flat.html

This official documentation from Sept 2019 states that "Starting with Magento 2.3.0+, the use of a flat catalog is no longer a best practice and is not recommended. Continued use of this feature is known to cause performance degradation and other indexing issues. A detailed description and solution is available in the Help Center."

Unfortunately this links to a Help Centre page which contradicts the information saying this affects "Magento Commerce (On-Premise) 2.1.x and above", despite the page being dated October 09, 2019. There are also other pages in the documentation that still recommend using flat catalog.

So which is it? This is a pretty key configuration setting from my experience and there needs to be a clear line of when to use it and when not to and more importantly why, what are the implications?

Does anyone here have any investigation results or metrics they can share to back up disabling these configurations ?

[Stuart M]

Flat Catalog has always been a topic of discusion as on small stores it can make a great performance gain but on larger stores and stores that grow over time it can become a major bottleneck at the database level if not kept in check.

The only reason Magento have changed their docs from saying 2.3+ to Any version is because some extensions on older versions of Magento have a requirement on flat tables existing.

Will get a message over to Magento for you though to review their documentation and see if they can update it to remove any abiguity between the docs and help center.

[Damian Culotta]

Hi @Stuart M!

Probably I'm missing something but where's the contradiction?

I mean, the documentation recommends to NOT use flat catalog because performance degradation.

Then, the Help Center is clear (I think).

Is on specific scenarios with specific (probably) modules. Right?

Also, regarding the Help Center page, as you said, was created on October but updated on Decemeber.

I'm interested in this topic. Based on what I saw and what I know and what I udnerstand, Flat catalog shouldn't be used as default rule.

I wasn't able to understand the opposite on those links.

Can you help me to see where the contradiction can be? (probably I'm missing somthing with the translation, sorry if that's the case)

[Stuart M]

He was talking about the fact docs say Magento 2.3 + and Help Center says ALL Magento versions.

I think he just wants clarification on if its 2.3+ or all (plugin dependant)

[Damian Culotta]

Now I see (thank you).

Probably the best way should be to explicitly mention the right version numbers. I can agree with that.

In the other hand, if we follow this reference https://magento.com/sites/default/files/magento-software-lifecycle-policy.pdf only Magento 2.3 should be the only valid referece (when we talk about Magento 2) so any possible referece to previous versions could be ignored. Right?

[jeff_matthews]

Sorry about the confusion @abscom. When the Documentation team that manages the user guide was first notified about the change in best practices, it was reported as specific to 2.3.x only.

Since a different team manages the Help Center, it appears that this was an oversight on our part and we failed to update the user guide with this new information after the publication of the Help Center article. We'll update the user guide to match the Help Center article as soon as we can.

Thanks for bringing this to our attention!

[ken_hicks]

Thanks for letting us know about the outdated information.  I've performed a keyword search and only found a few references to Flat Catalog.  If you know of additional topics, let me know.

The following files have been updated and will me merged and go live today, 2/5/2020:

• https://docs.magento.com/m2/ce/user_guide/catalog/catalog-flat.html

• https://docs.magento.com/m2/ce/user_guide/catalog/navigation-product-listings.html

• https://docs.magento.com/m2/ce/user_guide/configuration/catalog/catalog.html

Updates include:

- updated beginning note on Flat Catalog topic

- added "(not recommended)" to other references to Flat Catalog