# **DATE_ADD()**

## **Function Description**

``DATE_ADD()`` is used to perform date operations: ``DATE_ADD()`` function adds a specified time interval to a date. If ``date`` is ``NULL``, the function returns ``NULL``.

## **Function Syntax**

```text
> DATE_ADD(date,INTERVAL expr unit)
```

## **Parameter definition**

| Parameters | Description |
| ---- | ---- |
| date| Required parameters. The date parameter is a legal date expression. |
| expr | Required parameters. The expr parameter is the time interval that needs to be added to date. If expr is a negative number, it can start with "-". |
| unit| Required parameters. The unit parameter can be the following values: <br>MICROSECOND <br>SECOND<br>MINUTE<br>HOUR<br>DAY<br>WEEK<br>MONTH<br>QUA<br>TER<br>YEAR<br>SECOND_MICROSECOND<br>MINUTE_MICROSECOND<br>MINUTE_MICROSECOND<br>MINUTE_SECOND<br>HOUR_MICROSECOND<br>HOUR_MICROSECOND<br>HOUR_SECOND<br>HOUR_SECOND<br>HOUR_SECOND<br>HOUR_MINUTE<br>DAY_MICROSECOND<br>DAY_MICROSECOND<br>DAY_MICROSECOND<br>DAY_MICROSECOND<br>DAY_MICROSECOND<br>YEAR_MONTH|

## **Example**

```text
create table t2(orderid int, productname varchar(20), orderdate datetime);
insert into t2 values ('1','Jarl','2008-11-11 13:23:44.657');

mysql> SELECT OrderId,DATE_ADD(OrderDate,INTERVAL 45 DAY) AS OrderPayDate FROM t2;
+----------------------------------------+
| orderid | orderpaydate |
+----------------------------------------+
| 1 | 2008-12-26 13:23:45 |
+----------------------------------------+
```

## **limit**

Currently, the date format only supports the data formats of `yyyy-mm-dd` and `yyyymmdd`.