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Class: SchemaInferrer

Defined in: lang-sql/src/visitors/schema-inferrer.ts:46

Infers the schema of a logical plan. Each method returns external references.

Implements

SQLPlanVisitor<IdSet, IdSet>

Constructors

Constructor

new SchemaInferrer(vmap, db): SchemaInferrer

Defined in: lang-sql/src/visitors/schema-inferrer.ts:47

Parameters

Parameter	Type	Description
`vmap`	`Record`<`string`, `SQLPlanVisitor`<`IdSet`, `IdSet`>>	Per-language visitor map used to recurse into operators of other languages.
`db`	`DortDBAsFriend`	Database instance used to resolve nested language plan builders during visitLangSwitch.

Returns

SchemaInferrer

Properties

db

protected db: DortDBAsFriend

Defined in: lang-sql/src/visitors/schema-inferrer.ts:51

Database instance used to resolve nested language plan builders during visitLangSwitch.

vmap

protected vmap: Record<string, SQLPlanVisitor<IdSet, IdSet>>

Defined in: lang-sql/src/visitors/schema-inferrer.ts:49

Per-language visitor map used to recurse into operators of other languages.

Methods

getRelNames()

protected getRelNames(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:263

Walks up through projections and aliases to determine the set of relation names exposed by operator; used by visitCartesianProduct to detect duplicate table aliases and route schema attributes to the correct side.

Parameters

Parameter	Type
`operator`	`PlanTupleOperator`

Returns

Throws

If duplicate table aliases are found across a join.

inferSchema()

inferSchema(operator, ctx): [PlanOperator, IdSet]

Defined in: lang-sql/src/visitors/schema-inferrer.ts:62

Infers and finalises the schema of operator, resolving external attribute references and detecting ambiguous column names.

Parameters

Parameter	Type
`operator`	`PlanOperator`
`ctx`	`IdSet`

Returns

[PlanOperator, IdSet]

A tuple of the (possibly rewritten) root operator and the set of external references that must be satisfied by an enclosing scope.

Throws

If any column name is ambiguous across joined relations.

prefixTupleSourceAttrs()

protected prefixTupleSourceAttrs(operator): void

Defined in: lang-sql/src/visitors/schema-inferrer.ts:136

Inserts a plan.Projection above operator to strip relation-name prefixes from its attributes, replacing prefixed identifiers with their unqualified equivalents in the schema.

Parameters

Parameter	Type
`operator`	`TupleSource` \| `TupleFnSource`

Returns

void

processArg()

protected processArg(operator, arg, ctx): void

Defined in: lang-sql/src/visitors/schema-inferrer.ts:104

Adds arg to operator's schema - directly for identifiers, or by visiting sub-operators for plan nodes.

Parameters

Parameter	Type
`operator`	`PlanTupleOperator`
`arg`	`ASTIdentifier` \| `PlanOperator`
`ctx`	`IdSet`

Returns

void

processSetOp()

protected processSetOp(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:558

Infers schemas of both sides of a set operator and merges their external references.

Parameters

Parameter	Type
`operator`	`SetOperator`
`ctx`	`IdSet`

Returns

visitAggregate()

visitAggregate(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:590

Parameters

Parameter	Type
`operator`	`AggregateCall`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitAggregate

visitBidirectionalRecursion()

visitBidirectionalRecursion(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:754

Parameters

Parameter	Type
`operator`	`BidirectionalRecursion`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitBidirectionalRecursion

visitCalculation()

visitCalculation(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:236

Parameters

Parameter	Type
`operator`	`Calculation` \| `ItemFnSource` \| `TupleFnSource`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitCalculation

visitCartesianProduct()

visitCartesianProduct(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:331

Parameters

Parameter	Type
`operator`	`CartesianProduct`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitCartesianProduct

visitConditional()

visitConditional(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:252

Parameters

Parameter	Type
`operator`	`Conditional`

Returns

Implementation of

SQLPlanVisitor.visitConditional

visitDifference()

visitDifference(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:573

Parameters

Parameter	Type
`operator`	`Difference`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitDifference

visitDistinct()

visitDistinct(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:576

Parameters

Parameter	Type
`operator`	`Distinct`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitDistinct

visitFnCall()

visitFnCall(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:230

Parameters

Parameter	Type
`operator`	`FnCall`

Returns

Implementation of

SQLPlanVisitor.visitFnCall

visitGroupBy()

visitGroupBy(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:521

Parameters

Parameter	Type
`operator`	`GroupBy`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitGroupBy

visitIndexedRecursion()

visitIndexedRecursion(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:740

Parameters

Parameter	Type
`operator`	`IndexedRecursion`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitIndexedRecursion

visitIndexScan()

visitIndexScan(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:223

Parameters

Parameter	Type
`operator`	`IndexScan`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitIndexScan

visitIntersection()

visitIntersection(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:570

Parameters

Parameter	Type
`operator`	`Intersection`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitIntersection

visitItemFnSource()

visitItemFnSource(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:593

Parameters

Parameter	Type
`operator`	`ItemFnSource`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitItemFnSource

visitItemSource()

visitItemSource(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:227

Parameters

Parameter	Type
`operator`	`ItemSource`

Returns

Implementation of

SQLPlanVisitor.visitItemSource

visitJoin()

visitJoin(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:386

Parameters

Parameter	Type
`operator`	`Join`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitJoin

visitLangSwitch()

visitLangSwitch(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:693

Parameters

Parameter	Type
`operator`	`LangSwitch`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitLangSwitch

visitLimit()

visitLimit(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:553

Parameters

Parameter	Type
`operator`	`Limit`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitLimit

visitLiteral()

visitLiteral(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:233

Parameters

Parameter	Type
`operator`	`Literal`

Returns

Implementation of

SQLPlanVisitor.visitLiteral

visitMapFromItem()

visitMapFromItem(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:431

Parameters

Parameter	Type
`operator`	`MapFromItem`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitMapFromItem

visitMapToItem()

visitMapToItem(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:423

Parameters

Parameter	Type
`operator`	`MapToItem`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitMapToItem

visitNullSource()

visitNullSource(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:585

Parameters

Parameter	Type
`operator`	`NullSource`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitNullSource

visitOrderBy()

visitOrderBy(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:453

Parameters

Parameter	Type
`operator`	`OrderBy`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitOrderBy

visitProjection()

visitProjection(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:84

Parameters

Parameter	Type
`operator`	`Projection`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitProjection

visitProjectionConcat()

visitProjectionConcat(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:392

Parameters

Parameter	Type
`operator`	`ProjectionConcat`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitProjectionConcat

visitProjectionIndex()

visitProjectionIndex(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:442

Parameters

Parameter	Type
`operator`	`ProjectionIndex`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitProjectionIndex

visitQuantifier()

visitQuantifier(operator): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:641

Parameters

Parameter	Type
`operator`	`Quantifier`

Returns

Implementation of

SQLPlanVisitor.visitQuantifier

visitRecursion()

visitRecursion(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:120

Parameters

Parameter	Type
`operator`	`Recursion`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitRecursion

visitSelection()

visitSelection(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:115

Parameters

Parameter	Type
`operator`	`Selection`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitSelection

visitTableAlias()

visitTableAlias(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:168

Parameters

Parameter	Type
`operator`	`TableAlias`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitTableAlias

visitTupleFnSource()

visitTupleFnSource(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:596

Parameters

Parameter	Type
`operator`	`TupleFnSource`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitTupleFnSource

visitTupleSource()

visitTupleSource(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:202

Parameters

Parameter	Type
`operator`	`TupleSource`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitTupleSource

visitUnion()

visitUnion(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:567

Parameters

Parameter	Type
`operator`	`Union`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitUnion

visitUsing()

visitUsing(operator, ctx): IdSet

Defined in: lang-sql/src/visitors/schema-inferrer.ts:645

Parameters

Parameter	Type
`operator`	`Using`
`ctx`	`IdSet`

Returns

Implementation of

SQLPlanVisitor.visitUsing