Class Delta

All Implemented Interfaces:
Cloneable, RelOptNode, RelNode
Direct Known Subclasses:
LogicalDelta

public abstract class Delta
extends SingleRel
Relational operator that converts a relation to a stream.

For example, if Orders is a table, and TableScan(Orders) is a relational operator that returns the current contents of the table, then Delta(TableScan(Orders)) is a relational operator that returns all inserts into the table.

If unrestricted, Delta returns all previous inserts into the table (from time -∞ to now) and all future inserts into the table (from now to +∞) and never terminates.