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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.
4...
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...
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. ...
Inline instantiation of a constant List
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const is for compile-time constants. You could just make it static readonly, but that would only apply to the METRICS variable itself (which should typically be Metrics instead, by .NET naming conventions). It wouldn't make the list immutable - so someone could call METRICS.Add("sh...
How to search in array of object in mongodb
...', year:1975}}})
$elemMatch allows you to match more than one component within the same array element.
Without $elemMatch mongo will look for users with National Medal in some year and some award in 1975s, but not for users with National Medal in 1975.
See MongoDB $elemMatch Documentation for mo...