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What are the differences between a clustered and a non-clustered index?
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Clustered indexes physically order the data on the disk. This means no extra data is needed for the index, but there can be only one clustered index (obviously). Accessing data using a clustered index is fastest.
All other indexes must be non-clustered. A non-clustered index has a duplicate of ...
What is a WeakHashMap and when to use it? [duplicate]
...is good to implement canonical maps. Lets say you want to associate
some extra information to an object that you have a strong reference
to. You put an entry in a WeakHashMap with the object as the key, and
the extra information as the map value. Then, as long as you keep a
strong reference ...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
I am looking for a way to concatenate the strings of a field within a group by query. So for example, I have a table:
14 An...
ASP.NET MVC: Custom Validation by DataAnnotation
I have a Model with 4 properties which are of type string. I know you can validate the length of a single property by using the StringLength annotation. However I want to validate the length of the 4 properties combined.
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Escape quotes in JavaScript
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You need to escape the string you are writing out into DoEdit to scrub out the double-quote characters. They are causing the onclick HTML attribute to close prematurely.
Using the JavaScript escape character, \, isn't sufficient in the HTML contex...
Is it possible dynamically to add String to String.xml in Android?
Is it possible to have placeholders in string values in string.xml that can be assigned values at run time?
13 Answers
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How to create a .NET DateTime from ISO 8601 format
...le to parse only a limited subset of it. Especially it is a problem if the string contains time zone specification. (Neither it does for basic ISO8601 formats, or reduced precision formats - however this is not exactly your case.) That is why I make use of custom format strings when it comes to pars...
Why does PEP-8 specify a maximum line length of 79 characters? [closed]
...his millennium should Python PEP-8 specify a maximum line length of 79 characters?
9 Answers
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Removing double quotes from variables in batch file creates problems with CMD environment
...n extra double quote at the end, which is adding it back to the end of the string (after removing both quotes from the string).
Input:
set widget="a very useful item"
set widget
set widget=%widget:"=%
set widget
Output:
widget="a very useful item"
widget=a very useful item
Note: To replace Do...
python pandas: apply a function with arguments to a series
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Note: If you are passing a single string argument, for example 'abc', then args=('abc') will be evaluated as three arguments ('a', 'b', 'c'). To avoid this, you must pass a tuple containing the string, and to do that, include a trailing comma: args=('abc',)
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