Unique key that allows null vallues

[DavedT]

Hi all,

Is it possible to use two columns to create a unique key that allows nulls in one of the columns? Also is there any difference between unique and primary keys?

Nevermind sorry, I totally missed this while i was searching the forums:

Behavior Change Due to Unique Key Null Handling Bug Fix in 7.0

In MemSQL 6.8 and earlier, the code incorrectly handles NULL values in unique key columns for the case of a composite unique key, only in the case that the first column’s data type is defined to be NOT NULL but another column’s type is defined to be NULL. In MemSQL 7.0 we found this bug and fixed it, changing the behavior to follow the SQL standard [SQL13]. Application software should not rely on the old behavior present in MemSQL 6.8 when upgrading to 7.0 or later. To avoid confusion, MemSQL …

[MariaSilverhardt]

Thanks for using our forums to post your question DavedT!
Can you tell me the version number of the service you are using?

[DavedT]

Our singlestore DB version is 7.6.15.

[MariaSilverhardt]

Looks like you found a solution to your post. Woohoo! Super! Thanks for updating us .