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mysql 如何獲取 每天早上 9 點(diǎn)的 unix 時(shí)間戳？

1.各位大神，mysql 如何獲取 每天早上 9 點(diǎn)的 unix 時(shí)間戳啊，弄了好久都沒有成功

From [MySQLdiscussion group] 2017-04-17 13:59:37 0  3  732

Unable to establish external connection to MySQL/MariaDB database

I'm trying to connect a MariaDB client (DBeaver) to my database from my home computer. The IP address/host, po...

From [MySQLdiscussion group] 2024-03-31 23:39:43 0  1  731

How to use JOIN to perform DELETE operations in MySQL

I have the following query: deletefromcustomers_cardswhereidnotin(selectmin(id)fromcustomers_cardsgroupbynumbe...

From [MySQLdiscussion group] 2024-01-17 00:36:18 0  2  731

SQL query: What is the default sorting method?

What is the default sort order for queries when ORDERBY is not used?

From [MySQLdiscussion group] 2023-08-22 16:55:09 0  1  731

GROUP_CONCAT using the CASE statement can produce multiple outputs.

I have a SQL query that contains the following line of code: GROUP_CONCAT(CASE WHEN t3.ship=1 AND t4.item=0 TH...

From [MySQLdiscussion group] 2023-07-25 08:17:06 0  1  731

怎么寫mysql insert into select循環(huán)語句

SET @date='2016-11-09';INSERT INTO jia(山東) SELECT AVG(price) FROM jiagewang WHERE collecttime=@date AND provin...

From [MySQLdiscussion group] 2017-04-17 15:54:48 0  3  731

mysql - 刪除數(shù)據(jù)庫中的數(shù)據(jù)，但是表結(jié)構(gòu)保留

mysql如何捉到，刪除數(shù)據(jù)庫中的數(shù)據(jù)，但是表結(jié)構(gòu)保留每個(gè)表都清空數(shù)據(jù)，但是各個(gè)表的字段都保留。請問有20個(gè)表的話，就必須把說有的表名引用一遍？寫20遍？delete from tablename1；delete fro...

From [MySQLdiscussion group] 2017-04-17 15:31:58 0  7  731

The "where" statement in MySQL will interrupt the full connection

考慮以下表格：createtable`t1`(`date`date,`value`int);createtable`t2`(`date`date,`value`int);insertinto`t1`(`date`,`va...

From [MySQLdiscussion group] 2023-09-07 21:23:58 0  2  730

Create table using SELECT syntax in MySQL

I'm wondering how MySQL interprets CREATETABLEEsyntax:IfIwrite:CREATETABLEtbl1(`v1`int, `v2`intCONSTRAINTidxPR...

From [MySQLdiscussion group] 2023-07-20 22:47:01 0  1  730

mysql source命令如何把日志記錄到文件里面

mysql source命令如何把日志記錄到文件里面 在msyql數(shù)據(jù)庫備份過程中，使用source命令，日志都打印在界面上了，如何讓它輸入到一個(gè)文件里面？

From [MySQLdiscussion group] 2017-04-17 15:24:47 0  2  730

mysql - 為什么使用Group By對SQL的索引性能會(huì)有很大的影響

為什么使用Group By對SQL的索引性能會(huì)有很大的影響？索引是不是能提升group by的性能？ 還有一點(diǎn)關(guān)于SQL的疑問，為什么在使用模糊查詢的時(shí)候，%name%, 如果使用了前模糊，會(huì)使得索引沒有了效果，這個(gè)怎么...

From [MySQLdiscussion group] 2017-04-17 14:51:32 0  1  730

mysql - sql里面如何引用列的別名

描述： select column1+10 as c1,c1+10 as c2 from table1; 想實(shí)現(xiàn)上面的效果，結(jié)果在mysql里面報(bào)錯(cuò)了，提示找不到c1這個(gè)列; 但是select column1+10 as...

From [MySQLdiscussion group] 2017-04-17 11:34:30 0  4  730

分表 - mysql分庫后做關(guān)聯(lián)查詢的疑問？

是這樣的，我們的現(xiàn)在對數(shù)據(jù)庫做了水平拆分。把用戶和訂單分在兩個(gè)庫中，由于之前沒接觸過分庫，對關(guān)聯(lián)查詢有些疑問?，F(xiàn)在有一個(gè)需求，查詢所有用戶及其相關(guān)的訂單列表，首先查詢所有訂單，然后在根據(jù)每個(gè)訂單關(guān)...

From [MySQLdiscussion group] 2017-04-17 11:26:51 0  1  730

用navicat打開MySQL的表的時(shí)候，所有表都提示拒絕訪問，但是關(guān)閉提示后，又能打開，為什么會(huì)有這個(gè)提示？

From [MySQLdiscussion group] 2016-11-17 15:45:26 0  1  730

Retrieve the highest value in a column and its date

I have written code in MySQL to get the highest death value for various countries and their reporting date in ...

From [MySQLdiscussion group] 2024-04-02 15:26:37 0  1  729