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The guid data type

The guid (uuid, uniqueid) data type represents a 128-bit globally-unique value.


Currently support for the guid type is incomplete. The main gap is the lack of an index on columns of this type, affecting the performance of queries that predicate over this type. We strongly recommend that teams use values of type string instead.

guid literals

To represent a literal of type guid, use the following format:


The special form guid(null) represents the null value.