Hi, I have no idea how/if this is possible using the query protocol but I would try to parse the INSERT statement to get the table and columns names and then look up whether they are nullable in the information schema ( https://www.postgresql.org/docs/current/infoschema-columns.html)
Petr On Fri, Jun 27, 2025 at 4:31 PM Giacomo Cavalieri < giacomo.cavali...@icloud.com> wrote: > Hello! > I’m Giacomo, I’m the maintainer of < > https://github.com/giacomocavalieri/squirrel>, a tool that can generate > type safe bindings to run and decode the results of Postgres queries. It > does that by implementing the extended query protocol, which, among other > things, returns the OIDs of the query parameters’ types. > This is really handy and has worked great so far but I’m running into some > rough edges when it comes to the nullability of query parameters. > > Take a query like this one: > ``` > insert into some_table(not_null_col, nullable_column) > values ($1, $2) > ``` > It would be really handy to know that `$1` is being used as a non nullable > value, while `$2` could actually be null. Can this already be achieve > today, or would there be a way to surface this kind of information for > query parameters in the extended protocol? > > Sorry if this is not the proper list, I’m very new to all of this :) > Thanks! > > Giacomo >
