# **TO_SECONDS()**

## **Function Description**

The `TO_SECONDS(expr)` function is used to calculate the difference in seconds between a given date or date time expr and January 1, 0 AD 0:0:00. If `expr` is `NULL`, `NULL` is returned.

:::{note}
The `0000-00-00` and `0000-01-01` dates themselves are considered invalid. MatrixOne year query should start from `0001`. Query `0000-00-00` and `0000-01-01`, `TO_SECONDS()` returns the error message:

```text
mysql> SELECT TO_SECONDS('0000-00-00');
ERROR 20301 (HY000): invalid input: invalid datatime value 0000-00-00
mysql> SELECT TO_SECONDS('0000-01-01');
ERROR 20301 (HY000): invalid input: invalid datatime value 0000-01-01
```
:::
Similar to the `TO_DAYS()` function, for example, querying `SELECT TO_SECONDS('08-10-07');`, MatrixOne automatically completes year 08 to 0008, unlike MySQL. For more information, see [Double-digit Year in Date](../../Data-Types/date-time-data-types/year-type.md).

## **Function Syntax**

```text
> TO_SECONDS(expr)
```

`expr` is a date-time value, which can be of type `DATETIME`, `DATE` or `TIMESTAMP`.

## **Example**

```text
mysql> SELECT TO_SECONDS('0001-01-01');
+-----------------------------+
| to_seconds(0001-01-01) |
+-----------------------------+
| 31622400 |
+-----------------------------+
1 row in set (0.00 sec)

mysql> SELECT TO_SECONDS('2023-07-12 08:30:00');
+---------------------------------------+
| to_seconds(2023-07-12 08:30:00) |
+---------------------------------------+
| 63856369800 |
+---------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT TO_SECONDS('2007-10-07');
+-----------------------------+
| to_seconds(2007-10-07) |
+-----------------------------+
| 63358934400 |
+-----------------------------+
1 row in set (0.00 sec)

mysql> SELECT TO_SECONDS('97-10-07');
+--------------------------+
| to_seconds(97-10-07) |
+--------------------------+
| 3085257600 |
+--------------------------+
1 row in set (0.00 sec)
```