builder

Documentation

Index

• func GetProject(root PlanNode) string
• func LookupFromWhere(database, table, shardkey string, where *sqlparser.Where, ...) ([]router.Segment, error)
• type AggregatePlan
  • func NewAggregatePlan(log *xlog.Log, exprs []sqlparser.SelectExpr, tuples, groups []selectTuple, ...) *AggregatePlan
  • func (p *AggregatePlan) Build() error
  • func (p *AggregatePlan) Empty() bool
  • func (p *AggregatePlan) GroupAggregators() []Aggregator
  • func (p *AggregatePlan) JSON() string
  • func (p *AggregatePlan) NormalAggregators() []Aggregator
  • func (p *AggregatePlan) ReWritten() sqlparser.SelectExprs
  • func (p *AggregatePlan) Type() ChildType
• type Aggregator
• type ChildPlan
• type ChildType
• type Comparison
• type Direction
• type JoinKey
• type JoinNode
  • func (j *JoinNode) Children() []ChildPlan
  • func (j *JoinNode) GetQuery() []xcontext.QueryTuple
  • func (j *JoinNode) Order() int
• type JoinStrategy
• type LimitPlan
  • func NewLimitPlan(log *xlog.Log, node *sqlparser.Limit) *LimitPlan
  • func (p *LimitPlan) Build() error
  • func (p *LimitPlan) JSON() string
  • func (p *LimitPlan) ReWritten() *sqlparser.Limit
  • func (p *LimitPlan) Type() ChildType
• type MergeNode
  • func (m *MergeNode) Children() []ChildPlan
  • func (m *MergeNode) GenerateFieldQuery() *sqlparser.ParsedQuery
  • func (m *MergeNode) GetQuery() []xcontext.QueryTuple
  • func (m *MergeNode) Order() int
• type OrderBy
• type OrderByPlan
  • func NewOrderByPlan(log *xlog.Log, node sqlparser.OrderBy, root PlanNode) *OrderByPlan
  • func (p *OrderByPlan) Build() error
  • func (p *OrderByPlan) JSON() string
  • func (p *OrderByPlan) Type() ChildType
• type PlanNode
  • func BuildNode(log *xlog.Log, router *router.Router, database string, ...) (PlanNode, error)
• type UnionNode
  • func (u *UnionNode) Children() []ChildPlan
  • func (u *UnionNode) GetQuery() []xcontext.QueryTuple
  • func (u *UnionNode) Order() int

Functions

func GetProject

func GetProject(root PlanNode) string

GetProject return the project which is used in explain.

func LookupFromWhere

func LookupFromWhere(database, table, shardkey string, where *sqlparser.Where, router *router.Router) ([]router.Segment, error)

LookupFromWhere used to get the routing from the where clause.

Types

type AggregatePlan

type AggregatePlan struct {

	// IsPushDown whether aggfunc can be pushed down.
	IsPushDown bool
	// contains filtered or unexported fields
}

AggregatePlan represents order-by plan.

func NewAggregatePlan

func NewAggregatePlan(log *xlog.Log, exprs []sqlparser.SelectExpr, tuples, groups []selectTuple, isPushDown bool) *AggregatePlan

NewAggregatePlan used to create AggregatePlan.

func (*AggregatePlan) Build

func (p *AggregatePlan) Build() error

Build used to build distributed querys.

func (*AggregatePlan) Empty

func (p *AggregatePlan) Empty() bool

Empty returns the aggregator number more than zero.

func (*AggregatePlan) GroupAggregators

func (p *AggregatePlan) GroupAggregators() []Aggregator

GroupAggregators returns the group aggregators.

func (*AggregatePlan) JSON

func (p *AggregatePlan) JSON() string

JSON returns the plan info.

func (*AggregatePlan) NormalAggregators

func (p *AggregatePlan) NormalAggregators() []Aggregator

NormalAggregators returns the aggregators.

func (*AggregatePlan) ReWritten

func (p *AggregatePlan) ReWritten() sqlparser.SelectExprs

ReWritten used to re-write the SelectExprs clause.

func (*AggregatePlan) Type

func (p *AggregatePlan) Type() ChildType

Type returns the type of the plan.

type Aggregator

type Aggregator struct {
	Field    string
	Index    int
	Type     sqltypes.AggrType
	Distinct bool
}

Aggregator tuple.

type ChildPlan

type ChildPlan interface {
	Build() error
	Type() ChildType
	JSON() string
}

ChildPlan interface.

type ChildType

type ChildType string

ChildType type.

const (
	// ChildTypeOrderby enum.
	ChildTypeOrderby ChildType = "ChildTypeOrderby"

	// ChildTypeLimit enum.
	ChildTypeLimit ChildType = "ChildTypeLimit"

	// ChildTypeAggregate enum.
	ChildTypeAggregate ChildType = "ChildTypeAggregate"
)

type Comparison

type Comparison struct {
	// index in left and right node's fields.
	Left, Right int
	Operator    string
	// left expr may in right node.
	Exchange bool
}

Comparison is record the sqlparser.Comparison info.

type Direction

type Direction string

Direction type.

const (
	// ASC enum.
	ASC Direction = "ASC"

	// DESC enum.
	DESC Direction = "DESC"
)

type JoinKey

type JoinKey struct {
	// field name.
	Field string
	// table name.
	Table string
	// index in the fields.
	Index int
}

JoinKey is the column info in the on conditions.

type JoinNode

type JoinNode struct {

	// Left and Right are the nodes for the join.
	Left, Right PlanNode
	// join strategy.
	Strategy JoinStrategy

	// Cols defines which columns from left or right results used to build the return result.
	// For results coming from left, the values go as -1, -2, etc. For right, they're 1, 2, etc.
	// If Cols is {-1, -2, 1, 2}, it means the returned result is {Left0, Left1, Right0, Right1}.
	Cols []int `json:",omitempty"`

	// eg: from t1 join t2 on t1.a=t2.b, 't1.a' put in LeftKeys, 't2.a' in RightKeys.
	LeftKeys, RightKeys []JoinKey
	// eg: t1 join t2 on t1.a>t2.a, 't1.a>t2.a' parse into CmpFilter.
	CmpFilter []Comparison

	// whether is left join.
	IsLeftJoin bool
	// whether the right node has filters in left join.
	HasRightFilter bool
	// record the `otherLeftJoin.left`'s index in left.fields.
	LeftTmpCols []int
	// record the `rightNull`'s index in right.fields.
	RightTmpCols []int

	// Vars defines the list of joinVars that need to be built
	// from the Left result before invoking the Right subqquery.
	Vars map[string]int
	// contains filtered or unexported fields
}

JoinNode cannot be pushed down.

func (*JoinNode) Children

func (j *JoinNode) Children() []ChildPlan

Children returns the children of the plan.

func (*JoinNode) GetQuery

func (j *JoinNode) GetQuery() []xcontext.QueryTuple

GetQuery used to get the Querys.

func (*JoinNode) Order

func (j *JoinNode) Order() int

Order satisfies the plannode interface.

type JoinStrategy

type JoinStrategy int

JoinStrategy is Join Strategy.

const (
	// Cartesian product.
	Cartesian JoinStrategy = iota
	// SortMerge Join.
	SortMerge
	// NestLoop Join.
	NestLoop
)

type LimitPlan

type LimitPlan struct {
	Offset int
	Limit  int
	// contains filtered or unexported fields
}

LimitPlan represents order-by plan.

func NewLimitPlan

func NewLimitPlan(log *xlog.Log, node *sqlparser.Limit) *LimitPlan

NewLimitPlan used to create LimitPlan.

func (*LimitPlan) Build

func (p *LimitPlan) Build() error

Build used to build distributed querys.

func (*LimitPlan) JSON

func (p *LimitPlan) JSON() string

JSON returns the plan info.

func (*LimitPlan) ReWritten

func (p *LimitPlan) ReWritten() *sqlparser.Limit

ReWritten used to re-write the limit clause.

func (*LimitPlan) Type

func (p *LimitPlan) Type() ChildType

Type returns the type of the plan.

type MergeNode

type MergeNode struct {

	// select ast.
	Sel sqlparser.SelectStatement

	// query and backend tuple
	Querys []xcontext.QueryTuple
	// querys with bind locations.
	ParsedQuerys []*sqlparser.ParsedQuery

	// Mode.
	ReqMode xcontext.RequestMode
	// contains filtered or unexported fields
}

MergeNode can be pushed down.

func (*MergeNode) Children

func (m *MergeNode) Children() []ChildPlan

Children returns the children of the plan.

func (*MergeNode) GenerateFieldQuery

func (m *MergeNode) GenerateFieldQuery() *sqlparser.ParsedQuery

GenerateFieldQuery generates a query with an impossible where. This will be used on the RHS node to fetch field info if the LHS returns no result.

func (*MergeNode) GetQuery

func (m *MergeNode) GetQuery() []xcontext.QueryTuple

GetQuery used to get the Querys.

func (*MergeNode) Order

func (m *MergeNode) Order() int

Order satisfies the plannode interface.

type OrderBy

type OrderBy struct {
	Field     string
	Table     string
	Direction Direction
}

OrderBy tuple.

type OrderByPlan

type OrderByPlan struct {

	// The indexes mark the fields to be removed.
	RemovedIdxs []int
	OrderBys    []OrderBy `json:"OrderBy(s)"`
	// contains filtered or unexported fields
}

OrderByPlan represents order-by plan.

func NewOrderByPlan

func NewOrderByPlan(log *xlog.Log, node sqlparser.OrderBy, root PlanNode) *OrderByPlan

NewOrderByPlan used to create OrderByPlan.

func (*OrderByPlan) Build

func (p *OrderByPlan) Build() error

Build used to build distributed querys.

func (*OrderByPlan) JSON

func (p *OrderByPlan) JSON() string

JSON returns the plan info.

func (*OrderByPlan) Type

func (p *OrderByPlan) Type() ChildType

Type returns the type of the plan.

type PlanNode

type PlanNode interface {
	Children() []ChildPlan

	GetQuery() []xcontext.QueryTuple

	Order() int
	// contains filtered or unexported methods
}

PlanNode interface.

func BuildNode

func BuildNode(log *xlog.Log, router *router.Router, database string, node sqlparser.SelectStatement) (PlanNode, error)

BuildNode used to build the plannode tree.

type UnionNode

type UnionNode struct {
	Left, Right PlanNode
	// Union Type.
	Typ string
	// contains filtered or unexported fields
}

UnionNode ... eg: select a, b from t1 union select t2.a,t3.b from t2 join t3 on t2.id=t3.id;

     PlanNode1
       /  \
      /    \
PlanNode2  PlanNode3

PlanNode1: UnionNode PlanNode2: MergeNode PlanNode3: JoinNode

       /  \
      /    \
MergeNode  MergeNode

PlanNode2 and PlanNode3 are two independent trees, and they are also the Left and Right of PlanNode1.

func (*UnionNode) Children

func (u *UnionNode) Children() []ChildPlan

Children returns the children of the plan.

func (*UnionNode) GetQuery

func (u *UnionNode) GetQuery() []xcontext.QueryTuple

GetQuery used to get the Querys.

func (*UnionNode) Order

func (u *UnionNode) Order() int

Order unreachable.