tickscript.select() function

tickscript.select() changes a column’s name and optionally applies an aggregate or selector function to values in the column.

TICKscript helper function

tickscript.select() is a helper function meant to replicate TICKscript operations like the following:

// Rename
query("SELECT x AS y")

// Aggregate and rename
query("SELECT f(x) AS y")

Function type signature

(<-tables: B, as: string, ?column: A, ?fn: (<-: B, column: A) => stream[C]) => stream[D] where A: Equatable, C: Record, D: Record

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Parameters

column

Column to operate on. Default is _value.

fn

Aggregate or selector function to apply.

as

({{< req >}}) New column name.

tables

Input data. Default is piped-forward data (<-).

Examples

• Change the name of the value column
• Change the name of the value column and apply an aggregate function
• Change the name of the value column and apply a selector function

Change the name of the value column

import "contrib/bonitoo-io/tickscript"
import "sampledata"

sampledata.int()
    |> tickscript.select(as: "example-name")

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Input data

Output data

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Change the name of the value column and apply an aggregate function

import "contrib/bonitoo-io/tickscript"
import "sampledata"

sampledata.int()
    |> tickscript.select(as: "sum", fn: sum)

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Input data

Output data

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Change the name of the value column and apply a selector function

import "contrib/bonitoo-io/tickscript"
import "sampledata"

sampledata.int()
    |> tickscript.select(as: "max", fn: max)

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Input data

Output data

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