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Why is it important to override GetHashCode when Equals method is overridden?
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Yes, it is important if your item will be used as a key in a dictionary, or HashSet<T>, etc - since this is used (in the absence of a custom IEqualityComparer<T>) to group items into buckets. If the hash-code for two i...
Amazon S3 Change file download name
I have files stored on S3 with a GUID as the key name.
7 Answers
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Alter Table Add Column Syntax
I'm trying to programmatically add an identity column to a table Employees. Not sure what I'm doing wrong with my syntax.
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How do I turn off Oracle password expiration?
...BA_USERS where username = '<username>';
Then you can change the limit to never expire using:
alter profile <profile_name> limit password_life_time UNLIMITED;
If you want to previously check the limit you may use:
select resource_name,limit from dba_profiles where profile='<profi...
MFC RadioButton用法详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...件定义Control变量或Value变量，每组只能定义一个）
BOOL m_Radio1;//对应于组 1 1
BOOL m_Radio3; //对应于组 2 1
BOOL m_Radio7; //对应于组 3 1
BOOL m_Radio9; //对应于组 4 1
CButton m_RBtGroup1; //对应于组 1 1
CButton m_RBtGroup2;...
When should I use uuid.uuid1() vs. uuid.uuid4() in python?
...ption you do not create too many of them at the same time). I wouldn't use it if it's important that there's no connection between the uuid and the computer, as the mac address gets used to make it unique across computers.
You can create duplicates by creating more than 214 uuid1 in less than 100ns...
Eclipse - no Java (JRE) / (JDK) … no virtual machine
...rying to get Eclipse v3.5 (Galileo) to re-run on my computer - I have run it before with no problems, but now I keep getting this error:
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Is it possible to have multiple statements in a python lambda expression?
... return l[1]
map(second_lowest, lst)
Q. Can you get the second lowest item from a lambda by sorting the list?
A. Yes. As alex's answer points out, sorted() is a version of sort that creates a new list, rather than sorting in-place, and can be chained. Note that this is probably what you shou...
How to read environment variables in Scala
In Java, reading environment variables is done with System.getenv() .
6 Answers
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What's the difference between the data structure Tree and Graph?
... direction (parent / child relationships) and don't contain cycles.
They fit with in the category of Directed Acyclic Graphs (or a DAG).
So Trees are DAGs with the restriction that a child can only have one parent.
One thing that is important to point out, Trees aren't a recursive data structure. ...