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Best data type to store money values in MySQL
I want to store many records in a MySQL database. All of them contains money values. But I don't know how many digits will be inserted for each one.
Which data type do I have to use for this purpose?
VARCHAR or INT (or other numeric data types)?
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How to change the order of DataFrame columns?
...mean(1))
http://pandas.pydata.org/pandas-docs/stable/dsintro.html#column-selection-addition-deletion
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how do I query sql for a latest record date for each user
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select t.username, t.date, t.value
from MyTable t
inner join (
select username, max(date) as MaxDate
from MyTable
group by username
) tm on t.username = tm.username and t.date = tm.MaxDate
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Best data type for storing currency values in a MySQL database
What is the best SQL data type for currency values? I'm using MySQL but would prefer a database independent type.
9 Answer...
Determine project root from a running node.js application
...es. The modules are loaded first, and thus at the top of this registry. By selecting the first element of the registry and returning the path before the 'node_modules' directory we are able to determine the root of the application.
It's just one line of code, but for simplicity's sake (my sake), I ...
Alter a MySQL column to be AUTO_INCREMENT
...ber between parenthesis does exactly nothing (well ok, almost nothing) for MySQL integer types. The only thing that may be influenced by the number is the display width, and it is up to the client to do that. But don't be deceived and think that it works like it does for VARCHAR and DECIMAL types - ...
Difference between jQuery parent(), parents() and closest() functions
I have been using jQuery for a while. I wanted to use the parent() selector. I also came up with the closest() selector. Could not find any difference between them. Is there any? If yes, what?
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Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法 - 爬虫/数据库 - 清...
select * from ( select * from tablexxx order by xxx desc ) where rownum <= N
oracle数据库不支持mysql中limit, top功能,但可以通过rownum来限制返回的结果集的行数,rownum并不是用户添加的字段,而是oracle系统自动添加的。
LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method ca
... where p.Serial == strItem
select p;
The problem arises because ToString() isn't really executed, it is turned into a MethodGroup and then parsed and translated to SQL. Since there is no ToString() equivalent, the expression fails.
Note:
Make sure ...
App Inventor 2 列表代码块 · App Inventor 2 中文网
...用给定的变量名称 item 来引用当前列表项。
此处 是有关如何使用该块的教程。
创建过滤列表
通过保持输入列表中的每个项目满足测试来创建一个新列表。
主体是一个布尔表达式，用于检查项目是否通过测试。
如果主体...