alt Hacker NewsI'm admittedly an ORM apologist [1], but a few of his points articulated as "deal breakers" aren't that bad imo:
- "the pernicious use of foreign keys [...] links between classes are [...] foreign keys" ==> that just sounds like schema normalization, which is usually a good thing?
- "bending over backwards [...] to generate SQL that runs efficiently" ==> the huge majority of ORM-driven queries are "select * from table where id in ..."; for the queries that are more complicated than that, then yes use SQL! That's allowed!
Folks who dislike ORMs seem to have this false dichotomy that "the ORM _must_ be used for all queries", which is a self-imposed/unpractical restriction.
- "dual schema dangers" ==> he's exactly right that database should own the schema definition, but then just codegen the entities from the db schema? That's your singular source of truth, no drift. You can do this with Hibernate, ActiveRecord, Joist, many ORMs.
- "Identities" ==> ironically I think ORMs (that use the unit of work pattern) actually have net-better DX here b/c you can hook up a graph of entities with just references.
I.e. hook up a book to its author w/o knowing their ids yet, which explicitly avoids the annoyance he mentions of doing a partial commit/going to the db to figure out "what value should I INSERT into in the book.author_id column?" (but my author is new) in the middle of your business logic that just wants to "create books".
- transactions ==> agreed that "transactions via annotations" ala JPA/Hibernate are terrible, but afaiu all "internet scale" apps these days do reads outside of transactions, and just use op-locking during the singular flush/commit step to the db.
Disclaimer I am sure I won't change anyone's minds :-)
Edit: in the HN comments, we're debating "the best way to generate SQL", which is fine, but imo it overlooks the biggest value for ORMs: enforcing business invariants.
I.e. yes a simple INSERT is trivial is write, "why have the ORM to that!", but are you going to enforce the same business logic in the 10 places you do `INSERT authors` in your codebase? And if the answer is "I write an single `insertAuthor` abstraction to enforce this" then you're half-way to writing an adhoc half-specified, bug-riddled version of what a reactive ORM like Joist will do for you. [2] :-)
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I have seen many ORM enjoyers argue the point about “you can just use SQL!” but I have never once seen an ORM enjoyer allow it, much less do it themselves in an actual codebase. They will time and time again prefer you write 100 lines of Typescript/Python for what could be achieved with 15 lines of SQL.
> Folks who dislike ORMs seem to have this false dichotomy that "the ORM _must_ be used for all queries", which is a self-imposed/unpractical restriction
my experience is the exact opposite. People who love and advocate the merits of ORM insist that everything be executed through ORM because it introduces too much complexity for them to blend handwritten SQL with the ORM generated queries
> the huge majority of ORM-driven queries are "select * from table where id in ..."; for the queries that are more complicated than that, then yes use SQL! That's allowed!
The issue is, your lowest value queries are always this type, then you get the 10-20 in any code base that are 100x more complex, and they are the ones your end users care about the most.
You end up with a 80/20 principal in the wrong way, it's great at producing queries that represent 20% of the value of your app, and awful for the 80% that define the core value of it.
> the huge majority of ORM-driven queries are "select * from table where id in ..."
From my experience, you are mistaken on that. Those queries mostly come with some joins, either necessary or not to represent the object, and that often could be avoided if the data wasn't mapped into some standard object.
The main problem of mixing sql and orm together is that most orms don't provide a way to do raw queries in a type safe manner that plays well with non-raw-sql queries.
> Folks who dislike ORMs seem to have this false dichotomy that "the ORM _must_ be used for all queries", which is a self-imposed/unpractical restriction.
I've always heard a major selling point of ORMs is "You don't have to write the actual SQL anymore"
Because of that, I tend to not trust people who use ORMs to even know how to write queries by hand in the first place
> "bending over backwards [...] to generate SQL that runs efficiently" ==> the huge majority of ORM-driven queries are "select * from table where id in ..."; for the queries that are more complicated than that, then yes use SQL! That's allowed!
This is exactly why I hate ORMs. As I always put it "ORMs make the easy stuff slightly easier, and they make the harder stuff way harder".
If you're just using an OEM for the "select * from table where ID in ...", then you're saving practically nothing by using an ORM - just learn to write SQL, because as you put it, you're going to have to use it anyway for places where it falls over. There are lighter weight options that do basic stuff like transaction management and binding result sets to object properties that are much less of a PITA than ORMs.
In practice I've seen people try to use the ORM features first for places that need complicated SQL (which is a reasonable assumption), only to waste a boatload of time before concluding the ORM makes stuff harder.