Method VisitJoinRelation

query/sql/sql_parser.go:752–815

*************** from clause ***************** VisitJoinRelation visits the node

(ctx *antlrgen.JoinRelationContext)

// VisitJoinRelation visits the node
func (v *ASTBuilder) VisitJoinRelation(ctx *antlrgen.JoinRelationContext) interface{} {
	v.Logger.Debugf("VisitJoinRelation: %s", ctx.GetText())

	location := v.getLocation(ctx)
	level, levelWith, levelQuery := v.getCtxLevels(v.SQL2AqlCtx)

	v.setCtxLevels(v.SQL2AqlCtx, level, levelWith, levelQuery)
	left, _ := v.Visit(ctx.GetLeft()).(tree.IRelation)

	var right tree.IRelation
	if ctx.CROSS() != nil {
		v.setCtxLevels(v.SQL2AqlCtx, level, levelWith, levelQuery)
		right, _ = v.VisitSampledRelation(ctx.GetRight().(*antlrgen.SampledRelationContext)).(tree.IRelation)
		join := tree.NewJoin(v.getLocation(ctx), tree.CROSS, left, right, nil)
		join.SetValue(fmt.Sprintf("Join: (%s)", v.getText(ctx.BaseParserRuleContext)))
		return join
	}

	var criteria tree.IJoinCriteria
	if ctx.NATURAL() != nil {
		if levelQuery != 0 {
			panic(fmt.Errorf("natural join not supported at subquery/withQuery at (line:%d, col:%d)",
				location.Line, location.CharPosition))
		}
		v.setCtxLevels(v.SQL2AqlCtx, level, levelWith, levelQuery)
		right, _ = v.VisitSampledRelation(ctx.GetRight().(*antlrgen.SampledRelationContext)).(tree.IRelation)
		criteria = tree.NewNaturalJoin()
	} else {
		v.setCtxLevels(v.SQL2AqlCtx, level, levelWith, levelQuery)
		right, _ = v.Visit(ctx.GetRightRelation()).(tree.IRelation)

		ctxJoinCriteria, ok := ctx.JoinCriteria().(*antlrgen.JoinCriteriaContext)
		if !ok {
			panic(fmt.Errorf("missing join criteria at (line:%d, col:%d)", location.Line, location.CharPosition))
		}
		if ctxJoinCriteria.ON() != nil {
			v.setCtxLevels(v.SQL2AqlCtx, level, levelWith, levelQuery)
			v.SQL2AqlCtx.exprCheck = true
			v.Visit(ctx.JoinCriteria().(*antlrgen.JoinCriteriaContext).
				BooleanExpression())
			v.SQL2AqlCtx.exprCheck = false
			joinOn, _ := v.Visit(ctx.JoinCriteria().(*antlrgen.JoinCriteriaContext).
				BooleanExpression()).(tree.IExpression)
			criteria = tree.NewJoinOn(joinOn)
		} else if ctxJoinCriteria.USING() != nil {
			ctxArr := ctx.JoinCriteria().(*antlrgen.JoinCriteriaContext).AllIdentifier()
			expressions := make([]*tree.Identifier, len(ctxArr))
			for i, c := range ctxArr {
				expressions[i], _ = v.Visit(c).(*tree.Identifier)
			}
			criteria = tree.NewJoinUsing(expressions)
		}
	}

	joinType := v.getJoinType(ctx)
	if joinType != tree.LEFT {
		panic(fmt.Errorf("join type %v not supported yet at (line:%d, col:%d)",
			tree.JoinTypes[joinType], location.Line, location.CharPosition))