大约有 5,880 项符合查询结果(耗时:0.0325秒) [XML]
Create boolean column in MySQL with false as default value?
I want to create a table in MySQL with a boolean column whose default value is false . But it's accepting NULL as default...
...
What do column flags mean in MySQL Workbench?
In MySQL Workbench table editor there are 7 column flags available: PK, NN, UQ, BIN, UN, ZF, AI.
3 Answers
...
Can I change a column from NOT NULL to NULL without dropping it?
Need to alter a table to allow nulls on a column -- but cant drop the column...can I do this? Was trying something like:
3...
MySQL case sensitive query [duplicate]
.... However it will return 'VALUE', 'value', 'VaLuE', etc…
SELECT * FROM `table` WHERE `column` = 'value'
The good news is that if you need to make a case-sensitive query, it is very easy to do using the BINARY operator, which forces a byte by byte comparison:
SELECT * FROM `table` WHERE BINARY ...
SQL Server : GROUP BY clause to get comma-separated values [duplicate]
...ECT ReportId, Email =
STUFF((SELECT ', ' + Email
FROM your_table b
WHERE b.ReportId = a.ReportId
FOR XML PATH('')), 1, 2, '')
FROM your_table a
GROUP BY ReportId
SQL fiddle demo
sha...
SQL: How to perform string does not equal
...
Try the following query
select * from table
where NOT (tester = 'username')
share
|
improve this answer
|
follow
|
...
正确重置MySQL密码 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...下面是错误答案:
首先停止MySQL服务,然后使用skip-grant-tables参数启动它:
shell> /etc/init.d/mysql stopshell> mysqld_safe --skip-grant-tables &
此时无需授权就可以进入到MySQL命令行,使用SQL重置MySQL密码:
UPDATE mysql.user SET Password=PASSWORD('......
正确重置MySQL密码 - 爬虫/数据库 - 清泛IT社区,为创新赋能!
...
下面是错误答案:首先停止MySQL服务,然后使用skip-grant-tables参数启动它:shell> /etc/init.d/mysql stopshell> mysqld_safe --skip-grant-tables &此时无需授权就可以进入到MySQL命令行,使用SQL重置MySQL密码:UPDATE mysql.user SET Password=PASSWORD(...
Is there any advantage of using map over unordered_map in case of trivial keys?
...f course) when using unordered_map instead of map in a main entity look-up table.
On the other hand, I found it was much slower at repeatedly inserting and removing elements. It's great for a relatively static collection of elements, but if you're doing tons of insertions and deletions the hashing ...
Sorting arrays in NumPy by column
...
You can sort on multiple columns as per Steve Tjoa's method by using a stable sort like mergesort and sorting the indices from the least significant to the most significant columns:
a = a[a[:,2].argsort()] # First sort doesn't need to be stable.
a = a[a[:,1].argsort(kind='mergesort')]
a = a[a[:,...