Struct args in Spanner queries

[ChengyuanZhao]

This will be available soon in spanner client lib. See for more detail: googleapis/google-cloud-java#3287

Perhaps wait for GA spanner client lib to add this functionality?

[artembilan]

We can add it even before to play and provide some feedback if that.

Only the problem that we can't release our GA without their GA.

[jabubake]

FYI, this feature is already available https://github.com/GoogleCloudPlatform/google-cloud-java/releases/tag/v0.52.0

[ChengyuanZhao]

@jabubake

How do people usually use the @Param tags with Struct and array types? For Spring Data query methods I think people use these tags on the right hand side of where-statements. like ... where colA = @valA and colB + colC < @val2 .

Users can't put arrays or Structs on the right sides of those where-statements, correct? If that's the case, then I'm not sure how this new struct-arg feature would fit in to spring data spanner..

@meltsufin FYI

[ChengyuanZhao]

https://cloud.google.com/spanner/docs/data-types

Looks like STRUCTs can be used in WHERE clauses with some caveats, so I think this is worth implementing support in our @Query annotated query methods.

The user can provide:

• a Struct typed arg, which would be directly bound to the tag like any other tag and param currently supported.
• a POJO, which we will use the same logic as our write-conversion for making mutations to construct a Struct to then bind to the tag.