Module plan 

The logical and physical plans.

Invariant: a physical plan is legal before it is fast. Every access path this planner produces returns exactly the rows a full scan of the same term would return, and every predicate a path consumes is either fully enforced by the path or left in the residual filter. A predicate that is neither is a wrong answer, so the two lists are built together and the compiler emits whatever is left over.

The phase-6 planner is deliberately minimal: FROM terms stay in written order, joins are nested loops, and the only paths are a full scan, a rowid lookup or range, and an index seek over an equality prefix with an optional range on the column after it. Cost is not modelled yet; a path is chosen because it is more selective by construction, not because a number said so.

Structs

IndexSeekBranch

One seek over an index, as a branch of an AccessPath::IndexSeekUnion.

Levers

Which planner optimizations are switched on.

PhysicalPlan

A physical plan for a read-only statement.

PlanLine

One line of EXPLAIN QUERY PLAN, and how deep in the tree it sits.

PlannedSource

One FROM term with the path chosen for it.

RangeBound

One end of a scan range.

RecursiveQueue

What a recursive CTE’s own ORDER BY, LIMIT and OFFSET mean to the loop that fills it.

VirtualChoice

What a module answered when it was shown the offer.

VirtualConstraint

One predicate offered to a module, with what it was made of.

Enums

AccessPath

How one FROM term’s rows are produced.

AggregationMode

How the rows are grouped and aggregated.

BoundKind

A comparison an access path can enforce.

Constants

ROWID_ENTRY_SLOT

The entry slot that stands for the row’s own key rather than a field.

Functions

calls_a_volatile_function

Reports whether an expression calls a function whose answer changes from one call to the next, such as random().

conjunction

Splits a predicate into the conjunction the offer is built from.

expression_holds_subquery

Returns whether an expression holds a subquery, anywhere beneath it.

is_outer

Returns whether a join keeps rows that match nothing on the other side.

is_repeatable_condition

Reports whether a condition may be tested more than once with the same answer each time.

plan_select_with

Plans a bound SELECT with some optimizations switched off.

split_conjunction

Splits a AND b AND c into its terms.

subquery_nodes

Returns the nodes for the subqueries a write uses as values: those in its WHERE, then those in its other expressions, at the top level.

unanswerable_index_hint

Returns the name of an INDEXED BY index that cannot answer its term.

write_path_with

Returns how an UPDATE or a DELETE should find the rows it touches, with some optimizations switched off. @param table - the table being written @param source_id - the source the filter’s columns are bound to @param filter - the WHERE clause, when there is one @param levers - which optimizations are on