Primary key design
Every Kudu table must declare a primary key comprised of one or more columns. Like an RDBMS primary key, the Kudu primary key enforces a uniqueness constraint. Attempting to insert a row with the same primary key values as an existing row results in a duplicate key error.
Primary key columns must be non-nullable, and may not be a boolean or floating-point type.
Once set during table creation, the set of columns in the primary key may not be altered.
Unlike an RDBMS, Kudu does not provide an explicit auto-incrementing column feature, so the application must always provide the full primary key during insert.
Columns which do not satisfy the uniqueness constraint can still be used as primary keys, by specifying them as non-unique primary keys.
Row delete and update operations must also specify the full primary key of the row to be changed. Kudu does not natively support range deletes or updates.
The primary key values of a column may not be updated after the row is inserted. However, the row may be deleted and re-inserted with the updated value.