---
title: Use multiple fields in a calculation
description: Query multiple fields, pivot results, and use multiple field values to calculate new values in query results.
url: https://docs.influxdata.com/influxdb/cloud/query-data/common-queries/multiple-fields-in-calculations/
estimated_tokens: 2594
product: InfluxDB Cloud (TSM)
version: cloud
---

# Use multiple fields in a calculation

To use values from multiple fields in a mathematic calculation, complete the following steps:

1. [Filter by fields required in your calculation](#filter-by-fields)
2. [Pivot fields into columns](#pivot-fields-into-columns)
3. [Perform the mathematic calculation](#perform-the-calculation)

## Filter by fields

Use [`filter()`](/flux/v0/stdlib/universe/filter/) to return only the fields necessary for your calculation. Use the [`or` logical operator](/flux/v0/spec/operators/#logical-operators) to filter by multiple fields.

The following example queries two fields, `A` and `B`:

```js
from(bucket: "example-bucket")
    |> range(start: -1m)
    |> filter(fn: (r) => r._field == "A" or r._field == "B")
```

This query returns one or more tables for each field. For example:

| _time | _field | _value |
| --- | --- | --- |
| 2021-01-01T00:00:00Z | A | 12.4 |
| 2021-01-01T00:00:15Z | A | 12.2 |
| 2021-01-01T00:00:30Z | A | 11.6 |
| 2021-01-01T00:00:45Z | A | 11.9 |

| _time | _field | _value |
| --- | --- | --- |
| 2021-01-01T00:00:00Z | B | 3.1 |
| 2021-01-01T00:00:15Z | B | 4.8 |
| 2021-01-01T00:00:30Z | B | 2.2 |
| 2021-01-01T00:00:45Z | B | 3.3 |

## Pivot fields into columns

Use [`pivot()`](/flux/v0/stdlib/universe/pivot/) to align multiple fields by time.

To correctly pivot on `_time`, points for each field must have identical timestamps. If timestamps are irregular or do not align perfectly, see [Normalize irregular timestamps](/influxdb/cloud/query-data/flux/manipulate-timestamps/#normalize-irregular-timestamps).

```js
// ...
  |> pivot(rowKey: ["_time"], columnKey: ["_field"], valueColumn: "_value")
```

Using the queried data [above](#filter-by-fields), this `pivot()` function returns:

| _time | A | B |
| --- | --- | --- |
| 2021-01-01T00:00:00Z | 12.4 | 3.1 |
| 2021-01-01T00:00:15Z | 12.2 | 4.8 |
| 2021-01-01T00:00:30Z | 11.6 | 2.2 |
| 2021-01-01T00:00:45Z | 11.9 | 3.3 |

## Perform the calculation

Use [`map()`](/flux/v0/stdlib/universe/map/) to perform the mathematic operation using column values as operands.

The following example uses values in the `A` and `B` columns to calculate a new `_value` column:

```js
// ...
    |> map(fn: (r) => ({ r with _value: r.A * r.B }))
```

Using the pivoted data above, this `map()` function returns:

| _time | A | B | _value |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 12.4 | 3.1 | 38.44 |
| 2021-01-01T00:00:15Z | 12.2 | 4.8 | 58.56 |
| 2021-01-01T00:00:30Z | 11.6 | 2.2 | 25.52 |
| 2021-01-01T00:00:45Z | 11.9 | 3.3 | 39.27 |

## Full example query

```js
from(bucket: "example-bucket")
    |> range(start: -1m)
    |> filter(fn: (r) => r._field == "A" or r._field == "B")
    |> pivot(rowKey: ["_time"], columnKey: ["_field"], valueColumn: "_value")
    |> map(fn: (r) => ({r with _value: r.A * r.B}))
```

[queries](/influxdb/cloud/tags/queries/)