1.2.3 Query tree node types: Query, RangeTblEntry, TargetEntry

After the Analyze stage from 1.2.2, the raw parse tree has become a Query tree. This section is about the shape of that result. How it differs from a raw parse tree, what abstraction sits at its core, and what assumptions the next stages (rewriter and planner) get to start from when they receive a Query tree. Tokens descend into catalog coordinates A raw parse tree and a Query tree are both trees, but they sit on different planes. A raw parse tree mirrors the syntactic structure of SQL text, so