mysql怎么获取时间戳的函数UNIX_TIMESTAMP?我们收集了网络上流行的各种关于获取UNIX_TIMESTAMP的方法总结。
CREATE TRIGGER cus_info_tbl_tr AFTER INSERT ON cus_info_tbl
FOR EACH ROW
INSERT INTO summary_tbl ( `school_id`, `province_id`, `city_id`, `year`, `month`, `day`, `hour`, `minute`, `first_time`, `intdate` ) VALUES
( NEW.school_id,
NEW.province_id,
NEW.city_id,
YEAR( NEW.date_call ),
MONTH( NEW.date_call ),
DAYOFMONTH( NEW.date_call ),
HOUR( NEW.date_call ),
MINUTE( NEW.date_call ),
NEW.first_time,
UNIX_TIMESTAMP( NEW.date_call )+28800
);
看到了吧,在这个时间戳后面再加上8个小时的秒数就搞定了,呵呵。
不过我在google的时候注意到有很多兄弟都反应UNIX_TIMESTAMP和php中的mktime得到的值是一样的,但是我这里却出现了问题,到现在也没有能够找到原因。
代码如下 | 复制代码 |
UNIX_TIMESTAMP(), UNIX_TIMESTAMP(date) |
若无参数调用,则返回一个Unix timestamp ('1970-01-01 00:00:00' GMT 之后的秒数) 作为无符号整数。若用date 来调用UNIX_TIMESTAMP(),它会将参数值以'1970-01-01 00:00:00' GMT后的秒数的形式返回。date 可以是一个DATE 字符串、一个 DATETIME字符串、一个 TIMESTAMP或一个当地时间的YYMMDD 或YYYMMDD格式的数字。
查询
mysql中UNIX_TIMESTAMP()函数的应用比较
应用:
代码如下 | 复制代码 |
SELECT( UNIX_TIMESTAMP(endtime)-UNIX_TIMESTAMP(startime) |
这里我们可以使用
FROM_UNIXTIME(unix_timestamp), FROM_UNIXTIME(unix_timestamp,format) 来格式化一个UNIX_TIMESTAMP()时间戳,它将返回'YYYY-MM-DD HH:MM:SS'或YYYYMMDDHHMMSS 格式值的 unix_timestamp参数表示,具体格式取决于该函数是否用在字符串中或是数字语境中。
若format 已经给出,则结果的格式是根据format 字符串而定。 format 可以包含同DATE_FORMAT() 函数输入项列表中相同的说明符。
代码如下 | 复制代码 |
mysql> Select FROM_UNIXTIME(875996580); -> '1997-10-04 22:23:00' mysql> Select FROM_UNIXTIME(875996580) + 0; -> 19971004222300 mysql> Select FROM_UNIXTIME(UNIX_TIMESTAMP(), -> '%Y %D %M %h:%i:%s %x'); -> '2003 6th August 06:22:58 2003' |
php中:time()
time -- 返回当前的 Unix 时间戳
strtotime() 也可以转换Unix 时间戳

MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.

MySQL is an open source relational database management system suitable for data storage, management, query and security. 1. It supports a variety of operating systems and is widely used in Web applications and other fields. 2. Through the client-server architecture and different storage engines, MySQL processes data efficiently. 3. Basic usage includes creating databases and tables, inserting, querying and updating data. 4. Advanced usage involves complex queries and stored procedures. 5. Common errors can be debugged through the EXPLAIN statement. 6. Performance optimization includes the rational use of indexes and optimized query statements.

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To optimize MySQL slow query, slowquerylog and performance_schema need to be used: 1. Enable slowquerylog and set thresholds to record slow query; 2. Use performance_schema to analyze query execution details, find out performance bottlenecks and optimize.

MySQL and SQL are essential skills for developers. 1.MySQL is an open source relational database management system, and SQL is the standard language used to manage and operate databases. 2.MySQL supports multiple storage engines through efficient data storage and retrieval functions, and SQL completes complex data operations through simple statements. 3. Examples of usage include basic queries and advanced queries, such as filtering and sorting by condition. 4. Common errors include syntax errors and performance issues, which can be optimized by checking SQL statements and using EXPLAIN commands. 5. Performance optimization techniques include using indexes, avoiding full table scanning, optimizing JOIN operations and improving code readability.


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