Class Delta

  • All Implemented Interfaces:
    java.lang.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.