# date_trunc function
Truncates a timestamp at the specified time component

> For the complete documentation index, see [llms.txt](https://preview.materialize.com/materialize/40269/llms.txt).


`date_trunc` computes _ts_val_'s "floor value" of the specified time component,
i.e. the largest time component less than or equal to the provided value.

To align values along arbitrary values, see [`date_bin`].

## Signatures



```mzsql
date_trunc ( '<time_unit>', <val> )

```

| Syntax element | Description |
| --- | --- |
| `'<time_unit>'` | The time unit to truncate to. Valid values: `microseconds`, `milliseconds`, `second`, `minute`, `hour`, `day`, `week`, `month`, `quarter`, `year`, `decade`, `century`, `millenium`.  |
| `<val>` | A [`timestamp`](https://preview.materialize.com/materialize/40269/markdown-docs/sql/types/timestamp/index.md), [`timestamp with time zone`](https://preview.materialize.com/materialize/40269/markdown-docs/sql/types/timestamp/index.md), or [`interval`](https://preview.materialize.com/materialize/40269/markdown-docs/sql/types/interval/index.md) value to truncate.  |


Parameter | Type | Description
----------|------|------------
_val_ | [`timestamp`], [`timestamp with time zone`], [`interval`] | The value you want to truncate.

### Return value

`date_trunc` returns the same type as _val_.

## Examples

```mzsql
SELECT date_trunc('hour', TIMESTAMP '2019-11-26 15:56:46.241150') AS hour_trunc;
```
```nofmt
          hour_trunc
-------------------------------
 2019-11-26 15:00:00.000000000
```

```mzsql
SELECT date_trunc('year', TIMESTAMP '2019-11-26 15:56:46.241150') AS year_trunc;
```
```nofmt
          year_trunc
-------------------------------
 2019-01-01 00:00:00.000000000
```

```mzsql
SELECT date_trunc('millennium', INTERVAL '1234 years 11 months 23 days 23:59:12.123456789') AS millennium_trunc;
```
```nofmt
          millennium_trunc
-------------------------------
 1000 years
```

[`date_bin`]: https://preview.materialize.com/materialize/40269/markdown-docs/sql/functions/date-bin/index.md
[`interval`]: https://preview.materialize.com/materialize/40269/markdown-docs/sql/types/interval/index.md
[`timestamp`]: https://preview.materialize.com/materialize/40269/markdown-docs/sql/types/timestamp/index.md
[`timestamp with time zone`]: https://preview.materialize.com/materialize/40269/sql/types/timestamptz