Expand description
Transformations that move relation expressions up (lifting) and down (pushdown) the tree.
Transformations inhabiting this module can be used both as part of a normalization pass and as a stand-alone optimization. The former is usually achieved by implementing a more restricted form of the latter.
Structsยง
- Projection
Lifting - Hoist projections through operators.
- Projection
Pushdown - Pushes projections down through other operators.