expression

package
v0.5.1 Latest Latest
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 Go to latest Published: Mar 5, 2019 License: Apache-2.0 Imports: 14 Imported by: 10

Documentation

Index

Constants

View Source 
const (
	// ConvertToBinary is a conversion to binary.
	ConvertToBinary = "binary"
	// ConvertToChar is a conversion to char.
	ConvertToChar = "char"
	// ConvertToNChar is a conversion to nchar.
	ConvertToNChar = "nchar"
	// ConvertToDate is a conversion to date.
	ConvertToDate = "date"
	// ConvertToDatetime is a conversion to datetune.
	ConvertToDatetime = "datetime"
	// ConvertToDecimal is a conversion to decimal.
	ConvertToDecimal = "decimal"
	// ConvertToJSON is a conversion to json.
	ConvertToJSON = "json"
	// ConvertToSigned is a conversion to signed.
	ConvertToSigned = "signed"
	// ConvertToUnsigned is a conversion to unsigned.
	ConvertToUnsigned = "unsigned"
)

Variables

View Source 
var (
	// ErrUnsupportedInOperand is returned when there is an invalid righthand
	// operand in an IN operator.
	ErrUnsupportedInOperand = errors.NewKind("right operand in IN operation must be tuple, but is %T")
	// ErrInvalidOperandColumns is returned when the columns in the left operand
	// and the elements of the right operand don't match.
	ErrInvalidOperandColumns = errors.NewKind("operand should have %d columns, but has %d")
)
View Source 
var ErrConvertExpression = errors.NewKind("expression '%v': couldn't convert to %v")

ErrConvertExpression is returned when a conversion is not possible.

View Source 
var ErrIndexOutOfBounds = errors.NewKind("unable to find field with index %d in row of %d columns")

ErrIndexOutOfBounds is returned when the field index is out of the bounds.

View Source 
var ErrNilOperand = errors.NewKind("nil operand found in comparison")

ErrNilOperand ir returned if some or both of the comparison's operands is nil.

Functions

func Inspect 

func Inspect(expr sql.Expression, f func(sql.Expression) bool)

Inspect traverses the plan in depth-first order: It starts by calling f(expr); expr must not be nil. If f returns true, Inspect invokes f recursively for each of the children of expr, followed by a call of f(nil).

func IsBinary 

func IsBinary(e sql.Expression) bool

IsBinary returns whether the expression is binary or not.

func IsUnary 

func IsUnary(e sql.Expression) bool

IsUnary returns whether the expression is unary or not.

func JoinAnd 

func JoinAnd(exprs ...sql.Expression) sql.Expression

JoinAnd joins several expressions with And.

func NewAnd 

func NewAnd(left, right sql.Expression) sql.Expression

NewAnd creates a new And expression.

func NewLike added in v0.2.0 

func NewLike(left, right sql.Expression) sql.Expression

NewLike creates a new LIKE expression.

func NewOr 

func NewOr(left, right sql.Expression) sql.Expression

NewOr creates a new Or expression.

func Walk 

func Walk(v Visitor, expr sql.Expression)

Walk traverses the plan tree in depth-first order. It starts by calling v.Visit(expr); expr must not be nil. If the visitor returned by v.Visit(expr) is not nil, Walk is invoked recursively with the returned visitor for each children of the expr, followed by a call of v.Visit(nil) to the returned visitor.

Types

type Alias 

type Alias struct {
	UnaryExpression
	// contains filtered or unexported fields
}

Alias is a node that gives a name to an expression.

func NewAlias 

func NewAlias(child sql.Expression, name string) *Alias

NewAlias returns a new Alias node.

func (*Alias) Eval 

func (e *Alias) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Alias) Name 

func (e *Alias) Name() string

Name implements the Nameable interface.

func (*Alias) String 

func (e *Alias) String() string

func (*Alias) TransformUp 

func (e *Alias) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Alias) Type 

func (e *Alias) Type() sql.Type

Type returns the type of the expression.

type And 

type And struct {
	BinaryExpression
}

And checks whether two expressions are true.

func (*And) Eval 

func (a *And) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*And) String 

func (a *And) String() string

func (*And) TransformUp 

func (a *And) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*And) Type 

func (*And) Type() sql.Type

Type implements the Expression interface.

type Arithmetic 

type Arithmetic struct {
	BinaryExpression
	// contains filtered or unexported fields
}

Arithmetic expressions (+, -, *, /, ...)

func NewArithmetic 

func NewArithmetic(left, right sql.Expression, op string) *Arithmetic

NewArithmetic creates a new Arithmetic sql.Expression.

func NewBitAnd 

func NewBitAnd(left, right sql.Expression) *Arithmetic

NewBitAnd creates a new Arithmetic & sql.Expression.

func NewBitOr 

func NewBitOr(left, right sql.Expression) *Arithmetic

NewBitOr creates a new Arithmetic | sql.Expression.

func NewBitXor 

func NewBitXor(left, right sql.Expression) *Arithmetic

NewBitXor creates a new Arithmetic ^ sql.Expression.

func NewDiv 

func NewDiv(left, right sql.Expression) *Arithmetic

NewDiv creates a new Arithmetic / sql.Expression.

func NewIntDiv 

func NewIntDiv(left, right sql.Expression) *Arithmetic

NewIntDiv creates a new Arithmetic div sql.Expression.

func NewMinus 

func NewMinus(left, right sql.Expression) *Arithmetic

NewMinus creates a new Arithmetic - sql.Expression.

func NewMod 

func NewMod(left, right sql.Expression) *Arithmetic

NewMod creates a new Arithmetic % sql.Expression.

func NewMult 

func NewMult(left, right sql.Expression) *Arithmetic

NewMult creates a new Arithmetic * sql.Expression.

func NewPlus 

func NewPlus(left, right sql.Expression) *Arithmetic

NewPlus creates a new Arithmetic + sql.Expression.

func NewShiftLeft 

func NewShiftLeft(left, right sql.Expression) *Arithmetic

NewShiftLeft creates a new Arithmetic << sql.Expression.

func NewShiftRight 

func NewShiftRight(left, right sql.Expression) *Arithmetic

NewShiftRight creates a new Arithmetic >> sql.Expression.

func (*Arithmetic) Eval 

func (a *Arithmetic) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Arithmetic) String 

func (a *Arithmetic) String() string

func (*Arithmetic) TransformUp 

func (a *Arithmetic) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Arithmetic) Type 

func (a *Arithmetic) Type() sql.Type

Type returns the greatest type for given operation.

type Between 

type Between struct {
	Val   sql.Expression
	Lower sql.Expression
	Upper sql.Expression
}

Between checks a value is between two given values.

func NewBetween 

func NewBetween(val, lower, upper sql.Expression) *Between

NewBetween creates a new Between expression.

func (*Between) Children 

func (b *Between) Children() []sql.Expression

Children implements the Expression interface.

func (*Between) Eval 

func (b *Between) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Between) IsNullable 

func (b *Between) IsNullable() bool

IsNullable implements the Expression interface.

func (*Between) Resolved 

func (b *Between) Resolved() bool

Resolved implements the Expression interface.

func (*Between) String 

func (b *Between) String() string

func (*Between) TransformUp 

func (b *Between) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Between) Type 

func (*Between) Type() sql.Type

Type implements the Expression interface.

type BinaryExpression 

type BinaryExpression struct {
	Left  sql.Expression
	Right sql.Expression
}

BinaryExpression is an expression that has two children.

func (*BinaryExpression) Children 

func (p *BinaryExpression) Children() []sql.Expression

Children implements the Expression interface.

func (*BinaryExpression) IsNullable 

func (p *BinaryExpression) IsNullable() bool

IsNullable returns whether the expression can be null.

func (*BinaryExpression) Resolved 

func (p *BinaryExpression) Resolved() bool

Resolved implements the Expression interface.

type Case added in v0.4.0 

type Case struct {
	Expr     sql.Expression
	Branches []CaseBranch
	Else     sql.Expression
}

Case is an expression that returns the value of one of its branches when a condition is met.

func NewCase added in v0.4.0 

func NewCase(expr sql.Expression, branches []CaseBranch, elseExpr sql.Expression) *Case

NewCase returns an new Case expression.

func (*Case) Children added in v0.4.0 

func (c *Case) Children() []sql.Expression

Children implements the sql.Expression interface.

func (*Case) Eval added in v0.4.0 

func (c *Case) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the sql.Expression interface.

func (*Case) IsNullable added in v0.4.0 

func (c *Case) IsNullable() bool

IsNullable implements the sql.Expression interface.

func (*Case) Resolved added in v0.4.0 

func (c *Case) Resolved() bool

Resolved implements the sql.Expression interface.

func (*Case) String added in v0.4.0 

func (c *Case) String() string

func (*Case) TransformUp added in v0.4.0 

func (c *Case) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the sql.Expression interface.

func (*Case) Type added in v0.4.0 

func (c *Case) Type() sql.Type

Type implements the sql.Expression interface.

type CaseBranch added in v0.4.0 

type CaseBranch struct {
	Cond  sql.Expression
	Value sql.Expression
}

CaseBranch is a single branch of a case expression.

type Comparer 

type Comparer interface {
	sql.Expression
	Compare(ctx *sql.Context, row sql.Row) (int, error)
	Left() sql.Expression
	Right() sql.Expression
}

Comparer implements a comparison expression.

type Convert 

type Convert struct {
	UnaryExpression
	// contains filtered or unexported fields
}

Convert represent a CAST(x AS T) or CONVERT(x, T) operation that casts x expression to type T.

func NewConvert 

func NewConvert(expr sql.Expression, castToType string) *Convert

NewConvert creates a new Convert expression.

func (*Convert) Eval 

func (c *Convert) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Convert) String 

func (c *Convert) String() string

Name implements the Expression interface.

func (*Convert) TransformUp 

func (c *Convert) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Convert) Type 

func (c *Convert) Type() sql.Type

Type implements the Expression interface.

type DefaultColumn added in v0.2.0 

type DefaultColumn struct {
	// contains filtered or unexported fields
}

DefaultColumn is an default expression of a column that is not yet resolved.

func NewDefaultColumn added in v0.2.0 

func NewDefaultColumn(name string) *DefaultColumn

NewDefaultColumn creates a new NewDefaultColumn expression.

func (*DefaultColumn) Children added in v0.2.0 

func (*DefaultColumn) Children() []sql.Expression

Children implements the sql.Expression interface. The function returns always nil

func (*DefaultColumn) Eval added in v0.2.0 

func (*DefaultColumn) Eval(ctx *sql.Context, r sql.Row) (interface{}, error)

Eval implements the sql.Expression interface. The function always panics!

func (*DefaultColumn) IsNullable added in v0.2.0 

func (*DefaultColumn) IsNullable() bool

IsNullable implements the sql.Expression interface. The function always panics!

func (*DefaultColumn) Name added in v0.2.0 

func (c *DefaultColumn) Name() string

Name implements the sql.Nameable interface.

func (*DefaultColumn) Resolved added in v0.2.0 

func (*DefaultColumn) Resolved() bool

Resolved implements the sql.Expression interface. The function returns always false

func (*DefaultColumn) String added in v0.2.0 

func (c *DefaultColumn) String() string

String implements the Stringer The function returns column's name (can be an empty string)

func (*DefaultColumn) TransformUp added in v0.2.0 

func (c *DefaultColumn) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the sql.Expression interface.

func (*DefaultColumn) Type added in v0.2.0 

func (*DefaultColumn) Type() sql.Type

Type implements the sql.Expression interface. The function always panics!

type Equals 

type Equals struct {
	// contains filtered or unexported fields
}

Equals is a comparison that checks an expression is equal to another.

func NewEquals 

func NewEquals(left sql.Expression, right sql.Expression) *Equals

NewEquals returns a new Equals expression.

func (*Equals) Compare 

func (c *Equals) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*Equals) Eval 

func (e *Equals) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Equals) Left 

func (c *Equals) Left() sql.Expression

Left implements Comparer interface

func (*Equals) Right 

func (c *Equals) Right() sql.Expression

Right implements Comparer interface

func (*Equals) String 

func (e *Equals) String() string

func (*Equals) TransformUp 

func (e *Equals) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Equals) Type 

func (*Equals) Type() sql.Type

Type implements the Expression interface.

type GetField 

type GetField struct {
	// contains filtered or unexported fields
}

GetField is an expression to get the field of a table.

func NewGetField 

func NewGetField(index int, fieldType sql.Type, fieldName string, nullable bool) *GetField

NewGetField creates a GetField expression.

func NewGetFieldWithTable 

func NewGetFieldWithTable(index int, fieldType sql.Type, table, fieldName string, nullable bool) *GetField

NewGetFieldWithTable creates a GetField expression with table name.

func (*GetField) Children 

func (*GetField) Children() []sql.Expression

Children implements the Expression interface.

func (*GetField) Eval 

func (p *GetField) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*GetField) Index 

func (p *GetField) Index() int

Index returns the index where the GetField will look for the value from a sql.Row.

func (*GetField) IsNullable 

func (p *GetField) IsNullable() bool

IsNullable returns whether the field is nullable or not.

func (*GetField) Name 

func (p *GetField) Name() string

Name implements the Nameable interface.

func (*GetField) Resolved 

func (p *GetField) Resolved() bool

Resolved implements the Expression interface.

func (*GetField) String 

func (p *GetField) String() string

func (*GetField) Table 

func (p *GetField) Table() string

Table returns the name of the field table.

func (*GetField) TransformUp 

func (p *GetField) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*GetField) Type 

func (p *GetField) Type() sql.Type

Type returns the type of the field.

func (*GetField) WithIndex 

func (p *GetField) WithIndex(n int) sql.Expression

WithIndex returns this same GetField with a new index.

type GetSessionField 

type GetSessionField struct {
	// contains filtered or unexported fields
}

GetSessionField is an expression that returns the value of a session configuration.

func NewGetSessionField 

func NewGetSessionField(name string, typ sql.Type, value interface{}) *GetSessionField

NewGetSessionField creates a new GetSessionField expression.

func (*GetSessionField) Children 

func (f *GetSessionField) Children() []sql.Expression

Children implements the sql.Expression interface.

func (*GetSessionField) Eval 

func (f *GetSessionField) Eval(*sql.Context, sql.Row) (interface{}, error)

Eval implements the sql.Expression interface.

func (*GetSessionField) IsNullable 

func (f *GetSessionField) IsNullable() bool

IsNullable implements the sql.Expression interface.

func (*GetSessionField) Resolved 

func (f *GetSessionField) Resolved() bool

Resolved implements the sql.Expression interface.

func (*GetSessionField) String 

func (f *GetSessionField) String() string

String implements the sql.Expression interface.

func (*GetSessionField) TransformUp 

func (f *GetSessionField) TransformUp(fn sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the sql.Expression interface.

func (*GetSessionField) Type 

func (f *GetSessionField) Type() sql.Type

Type implements the sql.Expression interface.

type GreaterThan 

type GreaterThan struct {
	// contains filtered or unexported fields
}

GreaterThan is a comparison that checks an expression is greater than another.

func NewGreaterThan 

func NewGreaterThan(left sql.Expression, right sql.Expression) *GreaterThan

NewGreaterThan creates a new GreaterThan expression.

func (*GreaterThan) Compare 

func (c *GreaterThan) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*GreaterThan) Eval 

func (gt *GreaterThan) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*GreaterThan) Left 

func (c *GreaterThan) Left() sql.Expression

Left implements Comparer interface

func (*GreaterThan) Right 

func (c *GreaterThan) Right() sql.Expression

Right implements Comparer interface

func (*GreaterThan) String 

func (gt *GreaterThan) String() string

func (*GreaterThan) TransformUp 

func (gt *GreaterThan) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*GreaterThan) Type 

func (*GreaterThan) Type() sql.Type

Type implements the Expression interface.

type GreaterThanOrEqual 

type GreaterThanOrEqual struct {
	// contains filtered or unexported fields
}

GreaterThanOrEqual is a comparison that checks an expression is greater or equal to another.

func NewGreaterThanOrEqual 

func NewGreaterThanOrEqual(left sql.Expression, right sql.Expression) *GreaterThanOrEqual

NewGreaterThanOrEqual creates a new GreaterThanOrEqual

func (*GreaterThanOrEqual) Compare 

func (c *GreaterThanOrEqual) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*GreaterThanOrEqual) Eval 

func (gte *GreaterThanOrEqual) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*GreaterThanOrEqual) Left 

func (c *GreaterThanOrEqual) Left() sql.Expression

Left implements Comparer interface

func (*GreaterThanOrEqual) Right 

func (c *GreaterThanOrEqual) Right() sql.Expression

Right implements Comparer interface

func (*GreaterThanOrEqual) String 

func (gte *GreaterThanOrEqual) String() string

func (*GreaterThanOrEqual) TransformUp 

func (gte *GreaterThanOrEqual) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*GreaterThanOrEqual) Type 

func (*GreaterThanOrEqual) Type() sql.Type

Type implements the Expression interface.

type In 

type In struct {
	// contains filtered or unexported fields
}

In is a comparison that checks an expression is inside a list of expressions.

func NewIn 

func NewIn(left sql.Expression, right sql.Expression) *In

NewIn creates a In expression.

func (*In) Children 

func (in *In) Children() []sql.Expression

Children implements the Expression interface.

func (*In) Compare 

func (c *In) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*In) Eval 

func (in *In) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*In) Left 

func (c *In) Left() sql.Expression

Left implements Comparer interface

func (*In) Right 

func (c *In) Right() sql.Expression

Right implements Comparer interface

func (*In) String 

func (in *In) String() string

func (*In) TransformUp 

func (in *In) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*In) Type 

func (*In) Type() sql.Type

Type implements the Expression interface.

type IsNull 

type IsNull struct {
	UnaryExpression
}

IsNull is an expression that checks if an expression is null.

func NewIsNull 

func NewIsNull(child sql.Expression) *IsNull

NewIsNull creates a new IsNull expression.

func (*IsNull) Eval 

func (e *IsNull) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*IsNull) IsNullable 

func (e *IsNull) IsNullable() bool

IsNullable implements the Expression interface.

func (IsNull) String 

func (e IsNull) String() string

func (*IsNull) TransformUp 

func (e *IsNull) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*IsNull) Type 

func (e *IsNull) Type() sql.Type

Type implements the Expression interface.

type LessThan 

type LessThan struct {
	// contains filtered or unexported fields
}

LessThan is a comparison that checks an expression is less than another.

func NewLessThan 

func NewLessThan(left sql.Expression, right sql.Expression) *LessThan

NewLessThan creates a new LessThan expression.

func (*LessThan) Compare 

func (c *LessThan) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*LessThan) Eval 

func (lt *LessThan) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the expression interface.

func (*LessThan) Left 

func (c *LessThan) Left() sql.Expression

Left implements Comparer interface

func (*LessThan) Right 

func (c *LessThan) Right() sql.Expression

Right implements Comparer interface

func (*LessThan) String 

func (lt *LessThan) String() string

func (*LessThan) TransformUp 

func (lt *LessThan) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*LessThan) Type 

func (*LessThan) Type() sql.Type

Type implements the Expression interface.

type LessThanOrEqual 

type LessThanOrEqual struct {
	// contains filtered or unexported fields
}

LessThanOrEqual is a comparison that checks an expression is equal or lower than another.

func NewLessThanOrEqual 

func NewLessThanOrEqual(left sql.Expression, right sql.Expression) *LessThanOrEqual

NewLessThanOrEqual creates a LessThanOrEqual expression.

func (*LessThanOrEqual) Compare 

func (c *LessThanOrEqual) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*LessThanOrEqual) Eval 

func (lte *LessThanOrEqual) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*LessThanOrEqual) Left 

func (c *LessThanOrEqual) Left() sql.Expression

Left implements Comparer interface

func (*LessThanOrEqual) Right 

func (c *LessThanOrEqual) Right() sql.Expression

Right implements Comparer interface

func (*LessThanOrEqual) String 

func (lte *LessThanOrEqual) String() string

func (*LessThanOrEqual) TransformUp 

func (lte *LessThanOrEqual) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*LessThanOrEqual) Type 

func (*LessThanOrEqual) Type() sql.Type

Type implements the Expression interface.

type Like added in v0.2.0 

type Like struct {
	BinaryExpression
	// contains filtered or unexported fields
}

Like performs pattern matching against two strings.

func (*Like) Eval added in v0.2.0 

func (l *Like) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the sql.Expression interface.

func (*Like) String added in v0.2.0 

func (l *Like) String() string

func (*Like) TransformUp added in v0.2.0 

func (l *Like) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the sql.Expression interface.

func (*Like) Type added in v0.2.0 

func (l *Like) Type() sql.Type

Type implements the sql.Expression interface.

type Literal 

type Literal struct {
	// contains filtered or unexported fields
}

Literal represents a literal expression (string, number, bool, ...).

func NewLiteral 

func NewLiteral(value interface{}, fieldType sql.Type) *Literal

NewLiteral creates a new Literal expression.

func (*Literal) Children 

func (*Literal) Children() []sql.Expression

Children implements the Expression interface.

func (*Literal) Eval 

func (p *Literal) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Literal) IsNullable 

func (p *Literal) IsNullable() bool

IsNullable implements the Expression interface.

func (*Literal) Resolved 

func (p *Literal) Resolved() bool

Resolved implements the Expression interface.

func (*Literal) String 

func (p *Literal) String() string

func (*Literal) TransformUp 

func (p *Literal) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Literal) Type 

func (p *Literal) Type() sql.Type

Type implements the Expression interface.

func (*Literal) Value 

func (p *Literal) Value() interface{}

Value returns the literal value.

type Not 

type Not struct {
	UnaryExpression
}

Not is a node that negates an expression.

func NewNot 

func NewNot(child sql.Expression) *Not

NewNot returns a new Not node.

func (*Not) Eval 

func (e *Not) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Not) String 

func (e *Not) String() string

func (*Not) TransformUp 

func (e *Not) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Not) Type 

func (e *Not) Type() sql.Type

Type implements the Expression interface.

type NotIn 

type NotIn struct {
	// contains filtered or unexported fields
}

NotIn is a comparison that checks an expression is not inside a list of expressions.

func NewNotIn 

func NewNotIn(left sql.Expression, right sql.Expression) *NotIn

NewNotIn creates a In expression.

func (*NotIn) Children 

func (in *NotIn) Children() []sql.Expression

Children implements the Expression interface.

func (*NotIn) Compare 

func (c *NotIn) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*NotIn) Eval 

func (in *NotIn) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*NotIn) Left 

func (c *NotIn) Left() sql.Expression

Left implements Comparer interface

func (*NotIn) Right 

func (c *NotIn) Right() sql.Expression

Right implements Comparer interface

func (*NotIn) String 

func (in *NotIn) String() string

func (*NotIn) TransformUp 

func (in *NotIn) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*NotIn) Type 

func (*NotIn) Type() sql.Type

Type implements the Expression interface.

type Or 

type Or struct {
	BinaryExpression
}

Or checks whether one of the two given expressions is true.

func (*Or) Eval 

func (o *Or) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Or) String 

func (o *Or) String() string

func (*Or) TransformUp 

func (o *Or) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Or) Type 

func (*Or) Type() sql.Type

Type implements the Expression interface.

type Regexp 

type Regexp struct {
	// contains filtered or unexported fields
}

Regexp is a comparison that checks an expression matches a regexp.

func NewRegexp 

func NewRegexp(left sql.Expression, right sql.Expression) *Regexp

NewRegexp creates a new Regexp expression.

func (*Regexp) Compare 

func (c *Regexp) Compare(ctx *sql.Context, row sql.Row) (int, error)

Compare the two given values using the types of the expressions in the comparison. Since both types should be equal, it does not matter which type is used, but for reference, the left type is always used.

func (*Regexp) Eval 

func (re *Regexp) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Regexp) Left 

func (c *Regexp) Left() sql.Expression

Left implements Comparer interface

func (*Regexp) Right 

func (c *Regexp) Right() sql.Expression

Right implements Comparer interface

func (*Regexp) String 

func (re *Regexp) String() string

func (*Regexp) TransformUp 

func (re *Regexp) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Regexp) Type 

func (*Regexp) Type() sql.Type

Type implements the Expression interface.

type Star 

type Star struct {
	Table string
}

Star represents the selection of all available fields. This is just a placeholder node, it will not actually be evaluated but converted to a series of GetFields when the query is analyzed.

func NewQualifiedStar 

func NewQualifiedStar(table string) *Star

NewQualifiedStar returns a new star expression only for a specific table.

func NewStar 

func NewStar() *Star

NewStar returns a new Star expression.

func (*Star) Children 

func (*Star) Children() []sql.Expression

Children implements the Expression interface.

func (*Star) Eval 

func (*Star) Eval(ctx *sql.Context, r sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*Star) IsNullable 

func (*Star) IsNullable() bool

IsNullable implements the Expression interface.

func (*Star) Resolved 

func (*Star) Resolved() bool

Resolved implements the Expression interface.

func (*Star) String 

func (s *Star) String() string

func (*Star) TransformUp 

func (s *Star) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*Star) Type 

func (*Star) Type() sql.Type

Type implements the Expression interface.

type Tuple 

type Tuple []sql.Expression

Tuple is a fixed-size collection of expressions. A tuple of size 1 is treated as the expression itself.

func NewTuple 

func NewTuple(exprs ...sql.Expression) Tuple

NewTuple creates a new Tuple expression.

func (Tuple) Children 

func (t Tuple) Children() []sql.Expression

Children implements the Expression interface.

func (Tuple) Eval 

func (t Tuple) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (Tuple) IsNullable 

func (t Tuple) IsNullable() bool

IsNullable implements the Expression interface.

func (Tuple) Resolved 

func (t Tuple) Resolved() bool

Resolved implements the Expression interface.

func (Tuple) String 

func (t Tuple) String() string

func (Tuple) TransformUp 

func (t Tuple) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (Tuple) Type 

func (t Tuple) Type() sql.Type

Type implements the Expression interface.

type UnaryExpression 

type UnaryExpression struct {
	Child sql.Expression
}

UnaryExpression is an expression that has only one children.

func (*UnaryExpression) Children 

func (p *UnaryExpression) Children() []sql.Expression

Children implements the Expression interface.

func (*UnaryExpression) IsNullable 

func (p *UnaryExpression) IsNullable() bool

IsNullable returns whether the expression can be null.

func (*UnaryExpression) Resolved 

func (p *UnaryExpression) Resolved() bool

Resolved implements the Expression interface.

type UnaryMinus added in v0.2.0 

type UnaryMinus struct {
	UnaryExpression
}

UnaryMinus is an unary minus operator.

func NewUnaryMinus added in v0.2.0 

func NewUnaryMinus(child sql.Expression) *UnaryMinus

NewUnaryMinus creates a new UnaryMinus expression node.

func (*UnaryMinus) Eval added in v0.2.0 

func (e *UnaryMinus) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)

Eval implements the sql.Expression interface.

func (*UnaryMinus) String added in v0.2.0 

func (e *UnaryMinus) String() string

func (*UnaryMinus) TransformUp added in v0.2.0 

func (e *UnaryMinus) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the sql.Expression interface.

func (*UnaryMinus) Type added in v0.2.0 

func (e *UnaryMinus) Type() sql.Type

Type implements the sql.Expression interface.

type UnresolvedColumn 

type UnresolvedColumn struct {
	// contains filtered or unexported fields
}

UnresolvedColumn is an expression of a column that is not yet resolved. This is a placeholder node, so its methods Type, IsNullable and Eval are not supposed to be called.

func NewUnresolvedColumn 

func NewUnresolvedColumn(name string) *UnresolvedColumn

NewUnresolvedColumn creates a new UnresolvedColumn expression.

func NewUnresolvedQualifiedColumn 

func NewUnresolvedQualifiedColumn(table, name string) *UnresolvedColumn

NewUnresolvedQualifiedColumn creates a new UnresolvedColumn expression with a table qualifier.

func (*UnresolvedColumn) Children 

func (*UnresolvedColumn) Children() []sql.Expression

Children implements the Expression interface.

func (*UnresolvedColumn) Eval 

func (*UnresolvedColumn) Eval(ctx *sql.Context, r sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*UnresolvedColumn) IsNullable 

func (*UnresolvedColumn) IsNullable() bool

IsNullable implements the Expression interface.

func (*UnresolvedColumn) Name 

func (uc *UnresolvedColumn) Name() string

Name implements the Nameable interface.

func (*UnresolvedColumn) Resolved 

func (*UnresolvedColumn) Resolved() bool

Resolved implements the Expression interface.

func (*UnresolvedColumn) String 

func (uc *UnresolvedColumn) String() string

func (*UnresolvedColumn) Table 

func (uc *UnresolvedColumn) Table() string

Table returns the table name.

func (*UnresolvedColumn) TransformUp 

func (uc *UnresolvedColumn) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*UnresolvedColumn) Type 

func (*UnresolvedColumn) Type() sql.Type

Type implements the Expression interface.

type UnresolvedFunction 

type UnresolvedFunction struct {

	// IsAggregate or not.
	IsAggregate bool
	// Children of the expression.
	Arguments []sql.Expression
	// contains filtered or unexported fields
}

UnresolvedFunction represents a function that is not yet resolved. This is a placeholder node, so its methods Type, IsNullable and Eval are not supposed to be called.

func NewUnresolvedFunction 

func NewUnresolvedFunction(
	name string,
	agg bool,
	arguments ...sql.Expression,
) *UnresolvedFunction

NewUnresolvedFunction creates a new UnresolvedFunction expression.

func (*UnresolvedFunction) Children 

func (uf *UnresolvedFunction) Children() []sql.Expression

Children implements the Expression interface.

func (*UnresolvedFunction) Eval 

func (*UnresolvedFunction) Eval(ctx *sql.Context, r sql.Row) (interface{}, error)

Eval implements the Expression interface.

func (*UnresolvedFunction) IsNullable 

func (*UnresolvedFunction) IsNullable() bool

IsNullable implements the Expression interface.

func (*UnresolvedFunction) Name 

func (uf *UnresolvedFunction) Name() string

Name implements the Nameable interface.

func (*UnresolvedFunction) Resolved 

func (*UnresolvedFunction) Resolved() bool

Resolved implements the Expression interface.

func (*UnresolvedFunction) String 

func (uf *UnresolvedFunction) String() string

func (*UnresolvedFunction) TransformUp 

func (uf *UnresolvedFunction) TransformUp(f sql.TransformExprFunc) (sql.Expression, error)

TransformUp implements the Expression interface.

func (*UnresolvedFunction) Type 

func (*UnresolvedFunction) Type() sql.Type

Type implements the Expression interface.

type Visitor 

type Visitor interface {
	// Visit method is invoked for each expr encountered by Walk.
	// If the result Visitor is not nul, Walk visits each of the children
	// of the expr with that visitor, followed by a call of Visit(nil)
	// to the returned visitor.
	Visit(expr sql.Expression) Visitor
}

Visitor visits exprs in the plan.

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