# Class Interval (3.7.0-rc)

3.7.0-rc 3.6.0 (latest) 3.5.0 3.4.0 3.3.0 3.2.0 2.48.0-rc 2.47.1 2.46.0 2.45.0 2.44.0 2.43.0 2.42.0 2.41.0 2.40.0 2.39.0 2.38.0 2.37.0 2.36.0 2.35.0 2.34.0 2.33.0 2.32.0 2.31.0 2.30.0 2.29.0 2.28.0 2.27.0 2.26.0 2.25.1 2.24.0 2.23.0 2.22.1 2.21.0 2.20.0 2.19.0 2.18.0 2.17.0 2.16.0 2.15.1 2.14.0 2.13.0 2.12.0 2.11.0 A representation of the Spanner INTERVAL type: The difference between two date/time values.

###### See Also

<https://cloud.google.com/spanner/docs/data-types#interval_type>

## Constructors

### Interval(Interval \&\&)

Regular value type, supporting copy, assign, move.

| **Parameter** ||
|---|---|
| **Name** | **Description** |
|   | `Interval &&` |

### Interval(Interval const \&)

Regular value type, supporting copy, assign, move.

| **Parameter** ||
|---|---|
| **Name** | **Description** |
|   | `Interval const &` |

### Interval()

Default construction yields a zero-length interval.

### Interval(std::int32_t, std::int32_t, std::int32_t, std::chrono::nanoseconds)

| **Parameters** ||
|---|---|
| **Name** | **Description** |
| `years` | `std::int32_t` |
| `months` | `std::int32_t` |
| `days` | `std::int32_t` |
| `offset` | `std::chrono::nanoseconds` |

### Interval(std::chrono::nanoseconds)

| **Parameter** ||
|---|---|
| **Name** | **Description** |
| `offset` | `std::chrono::nanoseconds` |

## Operators

### operator-() const

Adjust the interval so that 30-day periods are represented as months.
For example, maps "35 days" to "1 month 5 days".

| **Returns** ||
|---|---|
| **Type** | **Description** |
| `Interval` |   |

### operator=(Interval \&\&)

Regular value type, supporting copy, assign, move.

| **Parameter** ||
|---|---|
| **Name** | **Description** |
|   | `Interval &&` |

| **Returns** ||
|---|---|
| **Type** | **Description** |
| `Interval &` |   |

### operator=(Interval const \&)

Regular value type, supporting copy, assign, move.

| **Parameter** ||
|---|---|
| **Name** | **Description** |
|   | `Interval const &` |

| **Returns** ||
|---|---|
| **Type** | **Description** |
| `Interval &` |   |

### operator std::string() const

Conversion to a string using ISO8601 duration format.