I was reading the data encoding doc and had a question with the handling of SQL Null.
According to the doc,
CRDB encodes each row as if the columns where that row is null did not exist .If all of the columns in a column family are null, then the corresponding KV pair is suppressed
If I understand the example dump in the linked doc correctly, there won’t be a KV pair for the column with null value.
But how does this work with MVCC? What happens to the 2nd step in the following sequence of operations? Do you do nothing, or set a tombstone at T2?
- at time T1, set column C to Value1;
- at time T2, set column C to null;
- at time T3, set column C to Value2.