README
¶
Functions
Aggregation Functions
as_list
as_list(expr)
as_list(expr,max_count)
Aggregates all rows of a column into a single array. The argument max_count specifies the maximum length. If this parameter is omitted, a reasonable default is choosen.
first
first(expr)
Aggregates all rows of a column by picking the first one.
last
last(expr)
Aggregates all rows of a column by picking the last one.
filter
filter(aggr,cond)
This function applies the given aggregation function aggr only on those rows, specified by cond.
group_by
group_by(key,aggr)
group_by(key,aggr,max_count)
This function works like a mixture of GROUP BY and as_list(...).
This function applies the given aggregation function aggr grouped by key. The result is returned as array. The argument max_count specifies the maximum length. If this parameter is omitted, a reasonable default is choosen.
This function is to be used instead of as_list(...), if the user wishes a deduplicated array:
group_by(my_column,first(my_column))
Regular functions
dict
dict(key1,value1,key2,value2,...)
This function creates a JSON-Style Object. Names and values must be interleaved.
array
array(value1,value2,value3)
This function creates a JSON-Style Array.
Documentation
¶
Index ¶
- Variables
- func Clone(o []sql.Expression) []sql.Expression
- func NewArray(exprs ...sql.Expression) (sql.Expression, error)
- func NewAsList(args ...sql.Expression) (sql.Expression, error)
- func NewDict(exprs ...sql.Expression) (sql.Expression, error)
- func NewFilter(args ...sql.Expression) (sql.Expression, error)
- func NewFirst(i sql.Expression) sql.Expression
- func NewGroupBy(args ...sql.Expression) (sql.Expression, error)
- func NewLast(i sql.Expression) sql.Expression
- func NewRowCluster(exprs ...sql.Expression) (sql.Expression, error)
- type Array
- func (a Array) Children() []sql.Expression
- func (a Array) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)
- func (a Array) IsNullable() bool
- func (a Array) Resolved() (ok bool)
- func (a Array) String() string
- func (a Array) TransformUp(f sql.TransformExprFunc) (_ sql.Expression, e error)
- func (a Array) Type() sql.Type
- type AsList
- func (a *AsList) Children() []sql.Expression
- func (a *AsList) Eval(_ *sql.Context, buffer sql.Row) (interface{}, error)
- func (a *AsList) IsNullable() bool
- func (a *AsList) Merge(ctx *sql.Context, buffer, partial sql.Row) error
- func (a *AsList) NewBuffer() sql.Row
- func (a *AsList) Resolved() (ok bool)
- func (a *AsList) String() string
- func (a *AsList) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (a *AsList) Type() sql.Type
- func (a *AsList) Update(ctx *sql.Context, buffer, row sql.Row) error
- type Dict
- func (a Dict) Children() []sql.Expression
- func (a Dict) Eval(ctx *sql.Context, row sql.Row) (interface{}, error)
- func (a Dict) IsNullable() bool
- func (a Dict) Resolved() (ok bool)
- func (a Dict) String() string
- func (a Dict) TransformUp(f sql.TransformExprFunc) (_ sql.Expression, e error)
- func (a Dict) Type() sql.Type
- type Filter
- func (a *Filter) Children() []sql.Expression
- func (a *Filter) Eval(_ *sql.Context, buffer sql.Row) (interface{}, error)
- func (a *Filter) IsNullable() bool
- func (a *Filter) Merge(ctx *sql.Context, buffer, partial sql.Row) error
- func (a *Filter) NewBuffer() sql.Row
- func (a *Filter) Resolved() (ok bool)
- func (a *Filter) String() string
- func (a *Filter) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (a *Filter) Type() sql.Type
- func (a *Filter) Update(ctx *sql.Context, buffer, row sql.Row) error
- type First
- func (a *First) Children() []sql.Expression
- func (a *First) Eval(_ *sql.Context, buffer sql.Row) (interface{}, error)
- func (a *First) IsNullable() bool
- func (a *First) Merge(ctx *sql.Context, buffer, partial sql.Row) error
- func (a *First) NewBuffer() sql.Row
- func (a *First) Resolved() (ok bool)
- func (a *First) String() string
- func (a *First) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (a *First) Type() sql.Type
- func (a *First) Update(ctx *sql.Context, buffer, row sql.Row) error
- type GroupBy
- func (a *GroupBy) Children() []sql.Expression
- func (a *GroupBy) Eval(ctx *sql.Context, buffer sql.Row) (_ interface{}, e error)
- func (a *GroupBy) IsNullable() bool
- func (a *GroupBy) Merge(ctx *sql.Context, buffer, partial sql.Row) error
- func (a *GroupBy) NewBuffer() sql.Row
- func (a *GroupBy) Resolved() (ok bool)
- func (a *GroupBy) String() string
- func (a *GroupBy) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (a *GroupBy) Type() sql.Type
- func (a *GroupBy) Update(ctx *sql.Context, buffer, row sql.Row) error
- type Last
- func (a *Last) Children() []sql.Expression
- func (a *Last) Eval(_ *sql.Context, buffer sql.Row) (interface{}, error)
- func (a *Last) IsNullable() bool
- func (a *Last) Merge(ctx *sql.Context, buffer, partial sql.Row) error
- func (a *Last) NewBuffer() sql.Row
- func (a *Last) Resolved() (ok bool)
- func (a *Last) String() string
- func (a *Last) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (a *Last) Type() sql.Type
- func (a *Last) Update(ctx *sql.Context, buffer, row sql.Row) error
- type RowCluster
- func (x RowCluster) Children() []sql.Expression
- func (RowCluster) Eval(*sql.Context, sql.Row) (interface{}, error)
- func (RowCluster) IsNullable() bool
- func (x RowCluster) Resolved() (ok bool)
- func (r RowCluster) String() string
- func (r RowCluster) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
- func (RowCluster) Type() sql.Type
Constants ¶
This section is empty.
Variables ¶
View Source
var Defaults = sql.Functions{ "row_cluster": sql.FunctionN(NewRowCluster), "as_list": sql.FunctionN(NewAsList), "first": sql.Function1(NewFirst), "last": sql.Function1(NewLast), "filter": sql.FunctionN(NewFilter), "group_by": sql.FunctionN(NewGroupBy), "dict": sql.FunctionN(NewDict), "array": sql.FunctionN(NewArray), }
Functions ¶
func Clone ¶
func Clone(o []sql.Expression) []sql.Expression
func NewArray ¶
func NewArray(exprs ...sql.Expression) (sql.Expression, error)
func NewAsList ¶
func NewAsList(args ...sql.Expression) (sql.Expression, error)
func NewDict ¶
func NewDict(exprs ...sql.Expression) (sql.Expression, error)
func NewFilter ¶
func NewFilter(args ...sql.Expression) (sql.Expression, error)
func NewFirst ¶
func NewFirst(i sql.Expression) sql.Expression
func NewGroupBy ¶
func NewGroupBy(args ...sql.Expression) (sql.Expression, error)
func NewLast ¶
func NewLast(i sql.Expression) sql.Expression
func NewRowCluster ¶
func NewRowCluster(exprs ...sql.Expression) (sql.Expression, error)
Types ¶
type Array ¶
type Array []sql.Expression
func (Array) TransformUp ¶
func (a Array) TransformUp(f sql.TransformExprFunc) (_ sql.Expression, e error)
Implements sql.Expression
type AsList ¶
type AsList struct {
// contains filtered or unexported fields
}
func (*AsList) Children ¶
func (a *AsList) Children() []sql.Expression
func (*AsList) IsNullable ¶
func (*AsList) TransformUp ¶
func (a *AsList) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
type Dict ¶
type Dict []sql.Expression
func (Dict) TransformUp ¶
func (a Dict) TransformUp(f sql.TransformExprFunc) (_ sql.Expression, e error)
Implements sql.Expression
type Filter ¶
type Filter struct {
Aggr sql.Aggregation
Expr sql.Expression
}
func (*Filter) Children ¶
func (a *Filter) Children() []sql.Expression
func (*Filter) IsNullable ¶
func (*Filter) TransformUp ¶
func (a *Filter) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
type First ¶
type First struct {
Expr sql.Expression
}
func (*First) Children ¶
func (a *First) Children() []sql.Expression
func (*First) IsNullable ¶
func (*First) TransformUp ¶
func (a *First) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
type GroupBy ¶
type GroupBy struct {
Expr sql.Expression
Aggr sql.Aggregation
Maximum uint64
}
func (*GroupBy) Children ¶
func (a *GroupBy) Children() []sql.Expression
func (*GroupBy) IsNullable ¶
func (*GroupBy) TransformUp ¶
func (a *GroupBy) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
type Last ¶
type Last struct {
Expr sql.Expression
}
func (*Last) Children ¶
func (a *Last) Children() []sql.Expression
func (*Last) IsNullable ¶
func (*Last) TransformUp ¶
func (a *Last) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
type RowCluster ¶
type RowCluster struct {
// contains filtered or unexported fields
}
func (RowCluster) Children ¶
func (x RowCluster) Children() []sql.Expression
Implements sql.Expression
func (RowCluster) TransformUp ¶
func (r RowCluster) TransformUp(st sql.TransformExprFunc) (sql.Expression, error)
Implements sql.Expression
Source Files
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