# JULIANDAY

> JULIANDAY function in StackQL: the fractional number of days since noon on 24 November 4714 BC for a time value, useful for date arithmetic.

Source: https://stackql.io/language-spec/functions/datetime/julianday

Returns the Julian day - the number of days since noon in Greenwich on November 24, 4714 B.C. [(Proleptic Gregorian calendar)](https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar).  

See also:  
[[` SELECT `]](/language-spec/select) [[ Date Modifiers ]](/language-spec/functions/datetime/date_modifiers) 

* * * 

## Syntax

```sql
SELECT JULIANDAY(datetime_expression [, modifier, ...]) FROM <multipartIdentifier>;
```

## Arguments

__*datetime_expression*__  
The datetime value.

__*modifier*__  
Zero or more modifiers to be applied to the *datetime_expression*.  For more information about modifiers, see [**Date Modifiers**](/language-spec/functions/datetime/date_modifiers)

## Return Value(s)

Returns the [Julian Day](https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar) representing the date component of the input *datetime_expression* with the *modifier* applied.

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## Examples

### Calculate the days between two dates

```sql
SELECT name, timeCreated,
round(julianday('now')-julianday(timeCreated)) as days_since
FROM google.storage.buckets WHERE project = 'stackql';
```

:::tip 

Use the [**ROUND**](/language-spec/functions/math/round) to convert floating point numbers to the nearest integer.

:::

For more information, see [https://www.sqlite.org/lang_datefunc.html](https://www.sqlite.org/lang_datefunc.html)