getColumn() function

The getColumn() function extracts a column from a table given its label. If the label is not present in the set of columns, the function errors.

*Function type: Stream and table*

getColumn(column: "_value")

Use tableFind() to extract a single table

getColumn() requires a single table as input. Use tableFind() to extract a single table from a stream of tables.

Parameters

column

Name of the column to extract.

*Data type: String*

Example

vs = from(bucket:"example-bucket")
    |> range(start: -5m)
    |> filter(fn:(r) => r._measurement == "cpu")
    |> tableFind(fn: (key) => key._field == "usage_idle")
    |> getColumn(column: "_value")
// Use column values
x = vs[0] + vs[1]

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