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Is an index needed for a primary key in SQLite?
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It does it for you.
INTEGER PRIMARY KEY columns aside, both UNIQUE and PRIMARY KEY
constraints are implemented by creating an index in the database (in
the same way as a "CREATE UNIQUE INDEX" statement would). Such an
index is used like any other index in the database to optimize
que...
Add a column with a default value to an existing table in SQL Server
... (0)--Optional Default-Constraint.
WITH VALUES --Add if Column is Nullable and you want the Default Value for Existing Records.
Notes:
Optional Constraint Name:
If you leave out CONSTRAINT D_SomeTable_SomeCol then SQL Server will autogenerate
a Default-Contraint with a funny Name like: DF__...
How to find all occurrences of a substring?
Python has string.find() and string.rfind() to get the index of a substring in a string.
20 Answers
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Negative weights using Dijkstra's Algorithm
I am trying to understand why Dijkstra's algorithm will not work with negative weights. Reading an example on Shortest Paths , I am trying to figure out the following scenario:
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Why aren't pointers initialized with NULL by default?
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We all realize that pointer (and other POD types) should be initialized.
The question then becomes 'who should initialize them'.
Well there are basically two methods:
The compiler initializes them.
The developer initializes them.
Let us assume tha...
Add a property to a JavaScript object using a variable as the name?
I'm pulling items out of the DOM with jQuery and want to set a property on an object using the id of the DOM element.
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Unable to authenticate with Git Bash to Visual Studio Team Services
I am unable to run any commands against my remote repository at Visual Studio Team Services (VSTS) because authentication fails.
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OwinStartup not firing
I had the OwinStartup configuration code working perfectly and then it stopped working. Unfortunately I'm not sure exactly what I did to get it to stop working and am having a really hard time figuring it out.
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How do I add multiple arguments to my custom template filter in a django template?
I looked into django's docs and book but only found example using a single argument... is it even possible?
9 Answers
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What are copy elision and return value optimization?
...to a copy or move constructor is elided, that constructor must still exist and must be accessible. This ensures that copy elision does not allow copying objects which are not normally copyable, e.g. because they have a private or deleted copy/move constructor.
C++17: As of C++17, Copy Elision is gua...