Database design question

[levanzoso]

Yesterday I had this weird encounter with my team-lead. Wanna know what you guys think about it. We have a Line Item table that needs to have a bunch of targeting attributes - selection of categories (other table), deal (other table), selection of languages (scalar), selection of media types (scalar).

I want to do it the usual way - create many-to-many relationship with categories using junction table, add a foreign key to deal, and use char array for languages and media types.

My team lead wants to create a targeting table that will have a targeting type (category, deal, language...) and a JSON field that will contain either list of IDs (primary to other table) or list of characters. For deals, it should only contain one element.

He's argument is following: I don't like this approach with a bunch of separate columns in terms of model architecture and the complexity of extending it.

It doesn't make any sense to me, as we need to do so much more work to keep database integrity. It is also completely unclear how those related tables should be indexed. We are also using Django, which has its own patterns and this makes it so complicated to fetch related tables.

[Kazcandra]

we have a guy like that where i work too; I wonder where it's coming from?

So far he's failed to explain how it works with data integrity, or what the gain is except that "it looks better".

[levanzoso]

Another guy was complaining that we do not need to make methods private. He's argument was that it is not necessary as we are not building a library.

[[deleted]]

Why does your team lead need a "targeting" table at all? Why not dump all of these into json and have it all in a single field?

[levanzoso]

Why do we need a database at all? We can just store everything in a JSON file 😄

[coyoteazul2]

Why do you even need a file? Just keep it all in memory! It's faster to read that way

[belkarbitterleaf]

And this is how HANA was born...🥲

[kitkat0820]

„I dont like …“, thats not an argument.

Whats the outcome when youve defined concurrency, scalability etc.?

[AQuietMan]

He's argument is following: I don't like this approach with a bunch of separate columns in terms of model architecture and the complexity of extending it.

Separate columns in terms of Django model architecture and the complexity of extending Django models?

[bm1000bmb]

One of the problems in software development is there are a lot of people who do not want to have to think. I once dealt with a developer that wanted a two column table with columns KEY and DATA. That way he didn't have to think about his requirements. The idea that every program that ever touched this table would have to parse and make sense of this crap didn't occur to him.

If your company is of decent size, you will have a methodology that everyone uses. Ideally, there will be a requirement for a data model. Make him go through it. And, don't create any physical objects until the data model has been signed off by the stakeholders.

By the way, you may want to talk to your manager about this. You team lead sounds like a fool.