Document supported data types

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Background

We should document which SQL Server data types are currently supported by this driver to document features/limitations. Any non-documented data type is not supported.

Problem

Right now, it’s not obvious which data types can be used and to which Java types SQL Server types map to.

Solution

Supported data types can be found by checking for Codec implementations in the io.r2dbc.mssql.codec package. Supported data types can be a table (matrix) between the SQL Server data type (e.g. VARCHAR) and to which Java type it maps to (e.g. java.lang.String, based on StringCodec.

The table with the type mapping should be added to our README.md.

Steps to fix

• Claim this issue with a comment below and ask any clarifying questions you need.
• Set up a repository locally following the Contributing Guidelines.
• Try to fix the issue following the steps above.
• Commit your changes and start a pull request.

Deliverables

• Updated README.md containing a section which SQL Server data types are currently supported by this driver.

[mp911de]

Consider it claimed. Let us know if you need any assistance.

[mp911de]

Thanks for reaching out. Big character data types are partially length-prefixed (see #28) and not yet supported. We should leave these out of the docs (not documented means unsupported) and we will document these once we have proper support for PLP types.