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by quietbritishjim 2743 days ago
Allow me to restate this question:

> Does it do that?

It was supposed to be clear from the context that this meant:

> Does building queries programmatically with SQLAlchemy do that?

Maybe I'm misreading your comment, but you seem to just be talking about writing queries directly in SQL.

If not, could you give an example/link of how to programmically build a query in SQLAlchemy that dynamically makes use of jsonb_array_elements? It would be hugely useful if I could do that.

2 comments

There are some old examples of how to use jsonb_array_elemens in SQLAlchemy here: https://github.com/sqlalchemy/sqlalchemy/issues/3566#issueco...
I was speaking of SQL, but if you can write it in SQL you can usually map it to SQLAlchemy. If worse comes to worse, you can use text() to drop down to raw SQL for just a portion of the query.

SQLAlchemy’s Postgres JSONB type allows subscription, so you can do Model.col[‘arrayfield’]. You can also manually invoke the operator with Model.col.op(‘->’)(‘arrayfield’).

So you should be able to do something like:

func.sum(func.jsonb_array_elements(Model.col.op(‘->’)(‘arrayfield’)).op(‘->’)(‘val’))

(Writing on my mobile without reference, so may not be fully accurate)