---
{
    "title": "week",
    "language": "en"
}
---

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# week
## Description
### Syntax

`INT WEEK(DATE date)`
`INT WEEK(DATE date, INT mode)`

Returns the week number for date.The value of the mode argument defaults to 0.
The following table describes how the mode argument works.
|Mode |First day of week |Range  |Week 1 is the first week …    |
|:----|:-----------------|:------|:-----------------------------|
|0    |Sunday            |0-53   |with a Sunday in this year    |
|1    |Monday            |0-53   |with 4 or more days this year |
|2    |Sunday            |1-53   |with a Sunday in this year    |
|3    |Monday            |1-53   |with 4 or more days this year |
|4    |Sunday            |0-53   |with 4 or more days this year |
|5    |Monday            |0-53   |with a Monday in this year    |
|6    |Sunday            |1-53   |with 4 or more days this year |
|7    |Monday            |1-53   |with a Monday in this year    |

The parameter is Date or Datetime type

## example
```
mysql> select week('2020-1-1');
+------------------+
| week('2020-1-1') |
+------------------+
|                0 |
+------------------+
```
```
mysql> select week('2020-7-1',1);
+---------------------+
| week('2020-7-1', 1) |
+---------------------+
|                  27 |
+---------------------+
```
## keyword
WEEK