Closed JanBaryla closed 1 year ago
It might be necessary to use *ewkb.GeometryCollection
(i.e. pointer to struct) not ewkb.GeometryCollection
. This allows the handling of nil
values (which are represented as NULL
in SQL). go-geom currently does not support NOT NULL
geometries.
There's a PostGIS example that includes an INSERT
statement.
Hope this helps. If the problem persists when using *ewkb.GeometryCollection
please could you share code that reproduces the problem - I'm not familiar with sqlboiler (but it looks like a really cool project!).
I see. You're right that nils might be tricky.
I'll see what I can do when it comes to that example, there's quite some boilerplate if you wanna use sqlboiler.
But it really just comes down to the fact that even though ewkb.GeometryCollection
appears to be implementing Value
, it actually doesn't (because of the pointers), and the Golang's standard library for database operations doesn't recognize it as a Valuer because of it (because instead of blindly calling Value
, it does the switch on type and tries checking the type)
It seems like in order to correctly implement the interface and keep things clean with nulls, one would have to add types like ewkb.NullGeometryCollection
.
It seems like in order to correctly implement the interface and keep things clean with nulls, one would have to add types like
ewkb.NullGeometryCollection
.
Yes, that makes sense. To be clear, it's only *ewkb.GeometryCollection
that implements sql/driver.Valuer
. ewkb.GeometryCollection
does not implement the interface.
If I remember correctly, when I first implemented this it just seemed simpler and without loss of functionality to implement nullable geometries by default, as I didn't see a strong reason to implement non-nullable geometries. That said, I would be very happy to add ewkb.NullGeometryCollection
and friends to go-geom. If we make any non-backwards-compatible changes then we can just bump the Go module's major version.
Hopefully this is now resolved. Please re-open if needed.
Hi,
lately I've been trying to get this library to work with sqlboiler, to basically teach it how to talk to PostGIS. Everything went pretty well, but when attempting to INSERT or UPDATE, this error https://github.com/golang/go/blob/master/src/database/sql/convert.go#L194 kept popping up.
Everything looked good, I didn't understand why the
Value
isn't called. I found out this switch statement https://github.com/golang/go/blob/2ebe77a2fda1ee9ff6fd9a3e08933ad1ebaea039/src/database/sql/driver/types.go#L241 doesn't detectewkb.GeometryCollection
that I was using as aValuer
.The fix I ended up doing is this: https://github.com/JanBaryla/go-geom/commit/daae2eef34b19e20253170ee1b0a5c0786cd04ac. Not quite sure what the consequences could be, though, so I'm opening an Issue instead of a PR.