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HashMap get/put complexity
...tant time... but you could have a hash which takes a long time to compute, and if there are multiple items in the hash map which return the same hash code, get will have to iterate over them calling equals on each of them to find a match.
In the worst case, a HashMap has an O(n) lookup due to walki...
append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
There is a case where a map will be constructed, and once it is initialized, it will never be modified again. It will however, be accessed (via get(key) only) from multiple threads. Is it safe to use a java.util.HashMap in this way?
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Best practice for Python assert
...l this an example of using them. This is more an example of properties in and of themselves: docs.python.org/library/functions.html#property
– Jason Baker
Jun 3 '09 at 13:43
3
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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...y.
Side effects are propagated to replicas too.
correction: both REPLACE and INSERT...ON DUPLICATE KEY UPDATE are non-standard, proprietary inventions specific to MySQL. ANSI SQL 2003 defines a MERGE statement that can solve the same need (and more), but MySQL does not support the MERGE statemen...
HTML table with 100% width, with vertical scroll inside tbody [duplicate]
How can I set for <table> 100% width and put only inside <tbody> vertical scroll for some height?
13 Answer...
multi-step registration process issues in asp.net mvc (split viewmodels, single model)
... [Required]
public string SomeOtherProperty { get; set; }
...
}
and so on. All those view models could be backed by a main wizard view model:
public class WizardViewModel
{
public Step1ViewModel Step1 { get; set; }
public Step2ViewModel Step2 { get; set; }
...
}
then you co...
What's the use of session.flush() in Hibernate
...) I have class where I am saving object using code id = session.save(obj); and transaction is committed at very next line but obj is not getting saved to DB ,Why? 2) I saved obj using session.save(obj); with commit and while returning I used return obj.getprimaryID(); In this case obj is saved to DB...
Using Build Flavors - Structuring source folders and build.gradle correctly
...ok at my IO talk you'll see how we mix in together values from the flavors and build type to create the variant.
For the Java source:
src/main/java
src/flavor1/java
src/debug/java
are all 3 used to create a single output. This means they can't define the same class.
If you want to have a differ...
Cannot use identity column key generation with ( TABLE_PER_CLASS )
...
The problem here is that you mix "table-per-class" inheritance and GenerationType.Auto.
Consider an identity column in MsSQL. It is column based. In a "table-per-class" strategy you use one table per class and each one has an ID.
Try:
@GeneratedValue(strategy = GenerationType.TABLE)
...