Add ConnectionMetadata.getDatabaseMajorVersion() and getDatabaseMinorVersion()

[lukaseder]

Feature Request

Is your feature request related to a problem? Please describe

When working with JDBC's DatabaseMetaData, I don't recall having ever used DatabaseMetaData.getDatabaseProductVersion(), which returns a string. The String is maybe useful to display in logs, or whatever, but in programmatic version specific logic, I've always appreciated the DatabaseMetaData.getDatabaseMajorVersion() and DatabaseMetaData.getDatabaseMinorVersion() methods much more. Querying them is much less error prone than relying on some string unformatting.

Describe the solution you'd like

Would be useful to have these methods also in R2DBC

Describe alternatives you've considered

Well, for now, I'll just parse the strings that the drivers offer me, or I ignore the versions.

Teachability, Documentation, Adoption, Migration Strategy

R2DBC tends to return nullable Integer types for compatibility reasons, so drivers can opt in to implementing these methods or just return null.

[mp911de]

Version numbers can be tricky because every server is doing versions differently (SQL Server 2018, version 14.00.3365, Postgres 13, version 13, and so on). We could follow the JDBC model and let drivers and consumers try to make sense out of the information.

It would be good to get a bit more opinions and how that information is used by folks that depend on the database version so we can come up with something useful.

[lukaseder]

Version numbers can be tricky because every server is doing versions differently (SQL Server 2018, version 14.00.3365, Postgres 13, version 13, and so on). We could follow the JDBC model and let drivers and consumers try to make sense out of the information.

Sure, it's weird. But it works in JDBC :)

It would be good to get a bit more opinions and how that information is used by folks that depend on the database version so we can come up with something useful.

Yeah, not the most pressing issue