[Doc]: Item types supported for arrays about doc HOT 7 OPEN

We should indeed provide a bit of documentation.

At the ADO level, Npgsql supports all the array capabilities of PostgreSQL itself, so in general what you find in the PostgreSQL docs is supported. Note that PostgreSQL does not support arrays of arrays, but does support multi-dimensional arrays (you can see some examples in the docs). You can use either .NET arrays or generic Lists to map to PostgreSQL arrays.

Note, however, that the EF Core provider's multi-dimensional arrays support is very limited - basically stick to one-dimensional arrays.

from doc.

Note that PostgreSQL does not support arrays of arrays, but does support multi-dimensional arrays (you can see some examples in the docs). You can use either .NET arrays or generic Lists to map to PostgreSQL arrays.

@roji Hey thanks for your answer! Much appreciated!

One thing though, when you're saying:

Note that PostgreSQL does not support arrays of arrays, but does support multi-dimensional arrays (you can see some examples in the docs)

How does it work in npgsql to benefit from the multidimensional array support then?

NpgsqlDbType.Array | NpgsqlDbType.Array | NpgsqlDbType.SmallInt

from doc.

Nope, just NpgsqlDbType.Array | NpgsqlDbType.SmallInt. That corresponds to an array of any dimensions in PostgreSQL.

from doc.

Nope, just NpgsqlDbType.Array | NpgsqlDbType.SmallInt. That corresponds to an array of any dimensions in PostgreSQL.

@roji Alright, that's a little bit counterintuitive... just to make this super-duper clear, with NpgsqlDbType.Array | NpgsqlDbType.SmallInt, you can pass resp. int[], int [,], int[,,], int[,,,] and even bigger dimensions?

from doc.

Yes. I know it may seem a bit odd, but the way PostgreSQL handles type arrays, all arrays of a given element type - regardless of dimension - are of a single type; this is why a single NpgsqlDbType value maps to them all.

from doc.

BTW regardless of PostgreSQL, NpgsqlDbType.Array | NpgsqlDbType.Array | NpgsqlDbType.SmallInt doesn't really make any sense in C# - ORing something will itself doesn't produce any useful effect.

from doc.

@roji alrite alrite, thanks! It makes sense now.

from doc.