Esempio n. 1
0
func (this *builder) VisitDelete(stmt *algebra.Delete) (interface{}, error) {
	this.cover = stmt
	this.where = stmt.Where()

	ksref := stmt.KeyspaceRef()
	keyspace, err := this.getNameKeyspace(ksref.Namespace(), ksref.Keyspace())
	if err != nil {
		return nil, err
	}

	err = this.beginMutate(keyspace, ksref, stmt.Keys(), stmt.Indexes(), stmt.Limit())
	if err != nil {
		return nil, err
	}

	subChildren := this.subChildren
	subChildren = append(subChildren, plan.NewSendDelete(keyspace, ksref.Alias(), stmt.Limit()))

	if stmt.Returning() != nil {
		subChildren = append(subChildren, plan.NewInitialProject(stmt.Returning()), plan.NewFinalProject())
	}

	parallel := plan.NewParallel(plan.NewSequence(subChildren...), this.maxParallelism)
	this.children = append(this.children, parallel)

	if stmt.Limit() != nil {
		this.children = append(this.children, plan.NewLimit(stmt.Limit()))
	}

	if stmt.Returning() == nil {
		this.children = append(this.children, plan.NewDiscard())
	}

	return plan.NewSequence(this.children...), nil
}
Esempio n. 2
0
func (this *builder) VisitUpsert(stmt *algebra.Upsert) (interface{}, error) {
	ksref := stmt.KeyspaceRef()
	ksref.SetDefaultNamespace(this.namespace)

	keyspace, err := this.getNameKeyspace(ksref.Namespace(), ksref.Keyspace())
	if err != nil {
		return nil, err
	}

	children := make([]plan.Operator, 0, 4)

	if stmt.Values() != nil {
		children = append(children, plan.NewValueScan(stmt.Values()))
		this.maxParallelism = util.MaxInt(1, len(stmt.Values()))
	} else if stmt.Select() != nil {
		sel, err := stmt.Select().Accept(this)
		if err != nil {
			return nil, err
		}

		children = append(children, sel.(plan.Operator))
	} else {
		return nil, fmt.Errorf("UPSERT missing both VALUES and SELECT.")
	}

	subChildren := make([]plan.Operator, 0, 4)
	subChildren = append(subChildren, plan.NewSendUpsert(keyspace, ksref.Alias(), stmt.Key(), stmt.Value()))

	if stmt.Returning() != nil {
		subChildren = append(subChildren, plan.NewInitialProject(stmt.Returning()), plan.NewFinalProject())
	} else {
		subChildren = append(subChildren, plan.NewDiscard())
	}

	parallel := plan.NewParallel(plan.NewSequence(subChildren...), this.maxParallelism)
	children = append(children, parallel)
	return plan.NewSequence(children...), nil
}
Esempio n. 3
0
func (this *builder) VisitSubselect(node *algebra.Subselect) (interface{}, error) {
	prevCover := this.cover
	prevCorrelated := this.correlated
	defer func() {
		this.cover = prevCover
		this.correlated = prevCorrelated
	}()

	this.correlated = node.IsCorrelated()

	if this.cover == nil {
		this.cover = node
	}

	aggs, err := allAggregates(node, this.order)
	if err != nil {
		return nil, err
	}

	this.where = node.Where()

	group := node.Group()
	if group == nil && len(aggs) > 0 {
		group = algebra.NewGroup(nil, nil, nil)
		this.where = constrainAggregate(this.where, aggs)
	}

	this.children = make([]plan.Operator, 0, 16)    // top-level children, executed sequentially
	this.subChildren = make([]plan.Operator, 0, 16) // sub-children, executed across data-parallel streams

	err = this.visitFrom(node, group)
	if err != nil {
		return nil, err
	}

	if this.coveringScan != nil {
		coverer := expression.NewCoverer(this.coveringScan.Covers())
		err = this.cover.MapExpressions(coverer)
		if err != nil {
			return nil, err
		}

		if this.where != nil {
			this.where, err = coverer.Map(this.where)
			if err != nil {
				return nil, err
			}
		}
	}

	if node.Let() != nil {
		this.subChildren = append(this.subChildren, plan.NewLet(node.Let()))
	}

	if node.Where() != nil {
		this.subChildren = append(this.subChildren, plan.NewFilter(node.Where()))
	}

	if group != nil {
		this.visitGroup(group, aggs)
	}

	projection := node.Projection()
	this.subChildren = append(this.subChildren, plan.NewInitialProject(projection))

	// Initial DISTINCT (parallel)
	if projection.Distinct() || this.distinct {
		this.subChildren = append(this.subChildren, plan.NewDistinct())
	}

	if !this.delayProjection {
		// Perform the final projection if there is no subsequent ORDER BY
		this.subChildren = append(this.subChildren, plan.NewFinalProject())
	}

	// Parallelize the subChildren
	this.children = append(this.children, plan.NewParallel(plan.NewSequence(this.subChildren...), this.maxParallelism))

	// Final DISTINCT (serial)
	if projection.Distinct() || this.distinct {
		this.children = append(this.children, plan.NewDistinct())
	}

	// Serialize the top-level children
	return plan.NewSequence(this.children...), nil
}
Esempio n. 4
0
func (this *builder) VisitMerge(stmt *algebra.Merge) (interface{}, error) {
	children := make([]plan.Operator, 0, 8)
	subChildren := make([]plan.Operator, 0, 8)
	source := stmt.Source()

	if source.Select() != nil {
		sel, err := source.Select().Accept(this)
		if err != nil {
			return nil, err
		}

		children = append(children, sel.(plan.Operator))
	} else {
		if source.From() == nil {
			return nil, fmt.Errorf("MERGE missing source.")
		}

		_, err := source.From().Accept(this)
		if err != nil {
			return nil, err
		}

		// Update local operator slices with results of building From:
		children = append(children, this.children...)
		subChildren = append(subChildren, this.subChildren...)

	}

	if source.As() != "" {
		subChildren = append(subChildren, plan.NewAlias(source.As()))
	}

	ksref := stmt.KeyspaceRef()
	ksref.SetDefaultNamespace(this.namespace)

	keyspace, err := this.getNameKeyspace(ksref.Namespace(), ksref.Keyspace())
	if err != nil {
		return nil, err
	}

	actions := stmt.Actions()
	var update, delete, insert plan.Operator

	if actions.Update() != nil {
		act := actions.Update()
		ops := make([]plan.Operator, 0, 5)

		if act.Where() != nil {
			ops = append(ops, plan.NewFilter(act.Where()))
		}

		ops = append(ops, plan.NewClone(ksref.Alias()))

		if act.Set() != nil {
			ops = append(ops, plan.NewSet(act.Set()))
		}

		if act.Unset() != nil {
			ops = append(ops, plan.NewUnset(act.Unset()))
		}

		ops = append(ops, plan.NewSendUpdate(keyspace, ksref.Alias(), stmt.Limit()))
		update = plan.NewSequence(ops...)
	}

	if actions.Delete() != nil {
		act := actions.Delete()
		ops := make([]plan.Operator, 0, 4)

		if act.Where() != nil {
			ops = append(ops, plan.NewFilter(act.Where()))
		}

		ops = append(ops, plan.NewSendDelete(keyspace, ksref.Alias(), stmt.Limit()))
		delete = plan.NewSequence(ops...)
	}

	if actions.Insert() != nil {
		act := actions.Insert()
		ops := make([]plan.Operator, 0, 4)

		if act.Where() != nil {
			ops = append(ops, plan.NewFilter(act.Where()))
		}

		ops = append(ops, plan.NewSendInsert(keyspace, ksref.Alias(), stmt.Key(), act.Value(), stmt.Limit()))
		insert = plan.NewSequence(ops...)
	}

	merge := plan.NewMerge(keyspace, ksref, stmt.Key(), update, delete, insert)
	subChildren = append(subChildren, merge)

	if stmt.Returning() != nil {
		subChildren = append(subChildren, plan.NewInitialProject(stmt.Returning()), plan.NewFinalProject())
	}

	parallel := plan.NewParallel(plan.NewSequence(subChildren...), this.maxParallelism)
	children = append(children, parallel)

	if stmt.Limit() != nil {
		children = append(children, plan.NewLimit(stmt.Limit()))
	}

	if stmt.Returning() == nil {
		children = append(children, plan.NewDiscard())
	}

	return plan.NewSequence(children...), nil
}