Module plan 

QueryPlan: the backend-neutral intermediate representation.

Every high-level query API compiles into a QueryPlan; backends compile a plan into SQL, a MongoDB pipeline, etc. Relational-only parts (joins, locking, DISTINCT ON) are reported through QueryPlan::required_features so they can be checked against BackendCapabilities before execution.

Structs

Compound

Another query combined with the plan by a SetOp.

JoinExpr

A join to another source (relational capability).

OrderExpr

One ordering term.

PlanOrigin

Identity of the database a subquery plan was built against.

QueryPlan

Backend-neutral read query.

QuerySource

What the query reads from.

SelectExpr

A projected expression.

Enums

DistinctMode

Distinct mode.

JoinKind

Join type.

LockMode

Row-lock request.

OrderDirection

Sort direction.

SetOp

How a query is combined with another one.