1.7 KiB
| title | description | aliases | menu | weight | |||||||
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| drop() function | The `drop()` function removes specified columns from a table. |
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The drop() function removes specified columns from a table.
Columns are specified either through a list or a predicate function.
When a dropped column is part of the group key, it will be removed from the key.
If a specified column is not present in a table, it will return an error.
Function type: Transformation
Output data type: Object
drop(columns: ["col1", "col2"])
// OR
drop(fn: (column) => column =~ /usage*/)
Parameters
{{% note %}}
Make sure fn parameter names match each specified parameter. To learn why, see Match parameter names.
{{% /note %}}
columns
Columns to be removed from the table.
Cannot be used with fn.
Data type: Array of strings
fn
A predicate function which takes a column name as a parameter (column) and returns
a boolean indicating whether or not the column should be removed from the table.
Cannot be used with columns.
Data type: Function
Examples
Drop a list of columns
from(bucket: "example-bucket")
|> range(start: -5m)
|> drop(columns: ["host", "_measurement"])
Drop columns matching a predicate
from(bucket: "example-bucket")
|> range(start: -5m)
|> drop(fn: (column) => column =~ /usage*/)