projection

Documentation

Index

• func MapExpressionToField(e impls.Expression, targetRelationName string, proj ProjectedExpression) impls.Expression
• func MapFieldToExpression(e impls.Expression, field fields.Field, target impls.Expression) impls.Expression
• type AliasedTable
• type ProjectedExpression
  • func ExpandProjection(fields []fields.Field, expressions []ProjectionExpression, ...) ([]ProjectedExpression, error)
  • func NewProjectedExpression(expression impls.Expression, alias string) ProjectedExpression
  • func NewProjectedExpressionFromField(field fields.Field) ProjectedExpression
  • func (p ProjectedExpression) String() string
• type Projection
  • func NewProjectionFromProjectedExpressions(targetRelationName string, projectedExpressions []ProjectedExpression) (*Projection, error)
  • func NewProjectionFromProjectionExpressions(targetRelationName string, relationFields []fields.Field, ...) (*Projection, error)
  • func (p *Projection) Aliases() []ProjectedExpression
  • func (p *Projection) DeprojectExpression(expression impls.Expression) impls.Expression
  • func (p *Projection) Fields() []fields.Field
  • func (p *Projection) Optimize(ctx impls.OptimizationContext)
  • func (p *Projection) ProjectExpression(expression impls.Expression) impls.Expression
  • func (p *Projection) String() string
• type ProjectionExpression
  • func NewAliasedExpression(expression impls.Expression, alias string) ProjectionExpression
  • func NewAliasedExpressionFromField(field fields.Field) ProjectionExpression
  • func NewTableWildcardProjectionExpression(relationName string) ProjectionExpression
  • func NewWildcardProjectionExpression() ProjectionExpression

Functions

func MapExpressionToField

func MapExpressionToField(e impls.Expression, targetRelationName string, proj ProjectedExpression) impls.Expression

func MapFieldToExpression

func MapFieldToExpression(e impls.Expression, field fields.Field, target impls.Expression) impls.Expression

Types

type AliasedTable

type AliasedTable struct {
	TableName string
	Alias     string
}

type ProjectedExpression

type ProjectedExpression struct {
	Expression impls.Expression
	Alias      string
}

func ExpandProjection

func ExpandProjection(fields []fields.Field, expressions []ProjectionExpression, aliasedTables ...AliasedTable) ([]ProjectedExpression, error)

func NewProjectedExpression

func NewProjectedExpression(expression impls.Expression, alias string) ProjectedExpression

func NewProjectedExpressionFromField

func NewProjectedExpressionFromField(field fields.Field) ProjectedExpression

func (ProjectedExpression) String

func (p ProjectedExpression) String() string

type Projection

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

func NewProjectionFromProjectedExpressions

func NewProjectionFromProjectedExpressions(
	targetRelationName string,
	projectedExpressions []ProjectedExpression,
) (*Projection, error)

func NewProjectionFromProjectionExpressions

func NewProjectionFromProjectionExpressions(
	targetRelationName string,
	relationFields []fields.Field,
	projectionExpressions []ProjectionExpression,
	aliasedTables ...AliasedTable,
) (*Projection, error)

func (*Projection) Aliases

func (p *Projection) Aliases() []ProjectedExpression

func (*Projection) DeprojectExpression

func (p *Projection) DeprojectExpression(expression impls.Expression) impls.Expression

func (*Projection) Fields

func (p *Projection) Fields() []fields.Field

func (*Projection) Optimize

func (p *Projection) Optimize(ctx impls.OptimizationContext)

func (*Projection) ProjectExpression

func (p *Projection) ProjectExpression(expression impls.Expression) impls.Expression

func (*Projection) String

func (p *Projection) String() string

type ProjectionExpression

type ProjectionExpression interface {
	Expand(fields []fields.Field, aliasedTables ...AliasedTable) ([]ProjectedExpression, error)
}

func NewAliasedExpression

func NewAliasedExpression(expression impls.Expression, alias string) ProjectionExpression

func NewAliasedExpressionFromField

func NewAliasedExpressionFromField(field fields.Field) ProjectionExpression

func NewTableWildcardProjectionExpression

func NewTableWildcardProjectionExpression(relationName string) ProjectionExpression

func NewWildcardProjectionExpression

func NewWildcardProjectionExpression() ProjectionExpression