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Using Left Outer joins with parent-child tables

A JOIN is used to combine rows from two or more tables, based on a related column between them. In a hierarchical table, the child table inherits the primary key columns of its parent table. This is done implicitly, without including the parent columns in the CREATE TABLE statement of the child. All tables in the hierarchy have the same shard key columns.

A Left Outer Join (LOJ) is one of the join operations that allows you to specify a join clause.