Simple filtering for JSON

[janpio]

Follow up to #186

[tomhoule]

We are working on implementing filtering (equality and non equality) on JSON fields in Postgres and MySQL (5.7 and 8). As far as I am aware, we don't have consensus on the implementation yet but we have multiple ways to implement it. One PR in this direction: prisma/prisma-engines#725

[tomhoule]

To clarify what we are currently looking into: this is only equals and not equals comparisons, so you would only be able to filter Json fields by comparing with an identical JSON value.

[radicand]

@tomhoule - so that I understand, if the DB has a row with a JSON field value of {"field":1, "anotherfield":2}, is this tracking just checking if the field is exactly that, or would something like checking if field1=1 be covered / match the row?

[tomhoule]

For the first version no, we would only be comparing against the whole JSON value. We definitely want to enable more operations like comparing specific paths in JSON objects, like your example, but that will come later.

[tomhoule]

I created an issue for more advanced JSON filtering: #2444

[do4gr]

Closing this since simple equality filtering for the complete Json is now implemented.