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How can I define a composite primary key in SQL?
...rID)
);
The pair (QuestionID,MemberID) must then be unique for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because...
How to implement a tree data-structure in Java? [closed]
Is there any standard Java library class to represent a tree in Java?
24 Answers
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ReSharper Abbreviations List: Where can I modify it?
I am using ReSharper 4.5, and what often happens when I am converting explicit properties into auto-properties, is that I will accidentally chose "Add XX to abbreviations list".
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How to bundle a native library and a JNI library inside a JAR?
...e in a static initializier of the main class to
calc the current os.arch and os.name
look for the library in the JAR file at the predefined location using Class.getResource(String)
if it exists, extract it to a temp file and load it with System.load(File).
I added functionality to do this for j...
How to remove leading and trailing whitespace in a MySQL field?
I have a table with two fields (countries and ISO codes):
11 Answers
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How to change column order in a table using sql query in sql server 2005?
...der there is recreating the table from scratch with a new CREATE TABLE command, copying over the data from the old table, and then dropping it.
There is no SQL command to define the column ordering.
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Correct way to quit a Qt program?
How should I quit a Qt Program, e.g when loading a data file, and discovered file corruption, and user need to quit this app or re-initiate data file?
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Are nullable types reference types?
...Guide):
Nullable types are instances of the System.Nullable struct.
and
Nullable types represent value-type variables that can be assigned the value of null. You cannot create a nullable type based on a reference type. (Reference types already support the null value.)
So, no they're not...
Identifying and removing null characters in UNIX
...icates that the file is encoded in UTF-16 and that you should use iconv to convert it to UTF-8.
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How can I reverse a NSArray in Objective-C?
... take advantage of the built-in reverseObjectEnumerator method on NSArray, and the allObjects method of NSEnumerator:
NSArray* reversedArray = [[startArray reverseObjectEnumerator] allObjects];
allObjects is documented as returning an array with the objects that have not yet been traversed with n...