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Microsoft ODBC Specification
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Do we need explicit null values for dynamic columns? #11

Closed mikepizzo closed 6 years ago

mikepizzo commented 8 years ago

Do we need to support explicit null values for dynamic columns (to distinguish null from not present)? If so, how do we delete a dynamic property? use special indicator value SQL_REMOVE_COLUMN, only available if SQL_DYNAMIC_COLUMNS is true? (and maybe not even then?) Make it an ODBC escape? Set a behavior?

jduo commented 7 years ago

It would be useful to be able to differentiate between explicit NULL and missing. When a user INSERTs a NULL, writing these as explicit NULLs takes up alot of space on the backend, but with ODBC 3.x there's no way to describe implicit NULL values.

mikepizzo commented 6 years ago

Differentiating null from absent would also require we have a way to differentiate in query. For example, where a column doesn't exist for a particular row.

mikepizzo commented 6 years ago

Don't differentiate a null value from a missing dynamic column. If a dynamic column is set to null it is effectively removed from the row.