MySQL EXTRACT 函数示例

摘要：在本教程中，您将学习如何使用 MySQL EXTRACT()函数提取DATE或DATETIME值的一部分。

MySQL `EXTRACT()`函数简介

EXTRACT()函数提取日期的一部分。下面说明了EXTRACT()函数的语法。

EXTRACT(unit FROM date)
Code language: SQL (Structured Query Language) (sql)

EXTRACT()函数需要两个参数unit和date 。

unit是您要从date中提取的间隔。以下是unit参数的有效间隔。

天
DAY_HOUR
DAY_MICROSECOND
DAY_MINUTE
DAY_SECOND
小时
小时_微秒
小时_分钟
HOUR_SECOND
微秒
分钟
分钟_微秒
分钟_秒
月
四分之一
第二
SECOND_微秒
星期
年
年_月

date是DATE或DATETIME值，您可以从中提取间隔。

MySQL EXTRACT 函数示例

从日期时间中提取日期：

mysql> SELECT EXTRACT(DAY FROM '2017-07-14 09:04:44') DAY;
+------+
| DAY  |
+------+
|   14 |
+------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 day_hour：

mysql> SELECT EXTRACT(DAY_HOUR FROM '2017-07-14 09:04:44') DAYHOUR;
+---------+
| DAYHOUR |
+---------+
|    1409 |
+---------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 day_microsecond：

mysql> SELECT EXTRACT(DAY_MICROSECOND FROM '2017-07-14 09:04:44') DAY_MS;
+----------------+
| DAY_MS         |
+----------------+
| 14090444000000 |
+----------------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 day_month：

mysql> SELECT EXTRACT(DAY_MINUTE FROM '2017-07-14 09:04:44') DAY_M;
+--------+
| DAY_M  |
+--------+
| 140904 |
+--------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 day_second

mysql> SELECT EXTRACT(DAY_SECOND FROM '2017-07-14 09:04:44') DAY_S;
+----------+
| DAY_S    |
+----------+
| 14090444 |
+----------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取小时：

mysql> SELECT EXTRACT(HOUR FROM '2017-07-14 09:04:44') HOUR;
+------+
| HOUR |
+------+
|    9 |
+------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 hour_microsecond：

mysql> SELECT EXTRACT(HOUR_MICROSECOND FROM '2017-07-14 09:04:44') HOUR_MS;
+-------------+
| HOUR_MS     |
+-------------+
| 90444000000 |
+-------------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 hour_min：

mysql> SELECT EXTRACT(HOUR_MINUTE FROM '2017-07-14 09:04:44') HOUR_M;
+--------+
| HOUR_M |
+--------+
|    904 |
+--------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取 hour_second：

mysql> SELECT EXTRACT(HOUR_SECOND FROM '2017-07-14 09:04:44') HOUR_S;
+--------+
| HOUR_S |
+--------+
|  90444 |
+--------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取微秒：

mysql> SELECT EXTRACT(MICROSECOND FROM '2017-07-14 09:04:44') MICROSECOND;
+-------------+
| MICROSECOND |
+-------------+
|           0 |
+-------------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取分钟：

mysql> SELECT EXTRACT(MINUTE FROM '2017-07-14 09:04:44') MINUTE;
+--------+
| MINUTE |
+--------+
|      4 |
+--------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取分钟_微秒：

mysql> SELECT EXTRACT(MINUTE_MICROSECOND FROM '2017-07-14 09:04:44') MINUTE_MS;
+-----------+
| MINUTE_MS |
+-----------+
| 444000000 |
+-----------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取分钟_秒：

mysql> SELECT EXTRACT(MINUTE_SECOND FROM '2017-07-14 09:04:44') MINUTE_S;
+----------+
| MINUTE_S |
+----------+
|      444 |
+----------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取月份：

mysql> SELECT EXTRACT(MONTH FROM '2017-07-14 09:04:44') MONTH;
+-------+
| MONTH |
+-------+
|     7 |
+-------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取四分之一：

mysql> SELECT EXTRACT(QUARTER FROM '2017-07-14 09:04:44') QUARTER;
+---------+
| QUARTER |
+---------+
|       3 |
+---------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取秒数：

mysql> SELECT EXTRACT(SECOND FROM '2017-07-14 09:04:44') SECOND;
+--------+
| SECOND |
+--------+
|     44 |
+--------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取第二微秒：

mysql> SELECT EXTRACT(SECOND_MICROSECOND FROM '2017-07-14 09:04:44') SECOND_MS;
+-----------+
| SECOND_MS |
+-----------+
|  44000000 |
+-----------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取周：

mysql> SELECT EXTRACT(WEEK FROM '2017-07-14 09:04:44') WEEK;
+------+
| WEEK |
+------+
|   28 |
+------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取年份：

mysql> SELECT EXTRACT(YEAR FROM '2017-07-14 09:04:44') YEAR;
+------+
| YEAR |
+------+
| 2017 |
+------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

从日期时间中提取year_month

mysql> SELECT EXTRACT(YEAR_MONTH FROM '2017-07-14 09:04:44') YEARMONTH;
+-----------+
| YEARMONTH |
+-----------+
|    201707 |
+-----------+
1 row in set (0.00 sec)
Code language: SQL (Structured Query Language) (sql)

在本教程中，您学习了如何使用 MySQL EXTRACT()函数提取DATE或DATETIME值的一部分。

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MySQL EXTRACT()函数简介

MySQL EXTRACT 函数示例

MySQL `EXTRACT()`函数简介