zoukankan      html  css  js  c++  java
  • MySQL基础函数

    /*NULL=======================================*/
    SELECT IFNULL(NULL,'IS NULL');
    #IS NULL
    
    /*date type==================================*/
    SELECT DATE_FORMAT(NOW(),'%Y-%m-%d %H:%i:%s');
    #2021-04-02 10:13:52
    
    SELECT STR_TO_DATE('2021-04-02','%Y-%m-%d');
    #2021-04-02
    
    SELECT UNIX_TIMESTAMP(NOW());
    #1617329776
    SELECT UNIX_TIMESTAMP('2021-04-02');
    #1617292800
    
    SELECT FROM_UNIXTIME(1617329776);
    #2021-04-02 10:16:16
    SELECT FROM_UNIXTIME(1617329776,'%Y-%m-%d %H:%i:%s');
    #2021-04-02 10:16:16
    
    SELECT DATE_ADD('2021-04-02',INTERVAL 1 day);
    #2021-04-03
    SELECT DATE_ADD(NOW(),INTERVAL 1 day);
    #2021-04-03 10:17:57
    
    SELECT DATEDIFF(NOW(),'2021-03-01');
    #32
    SELECT DATEDIFF('2021-04-02','2021-04-01');
    #1
    
    /*char type==================================*/
    SELECT CONCAT('hello','-',123);
    #hello-123
  • 相关阅读:
    doc
    doc
    doc
    doc
    doc
    doc
    doc
    doc
    java基础知识系列--- 反射,注解,泛型,内省
    CCProcxy代理服务器的配置使用
  • 原文地址:https://www.cnblogs.com/zenple/p/14677776.html
Copyright © 2011-2022 走看看