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How can one see the structure of a table in SQLite? [duplicate]
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Invoke the sqlite3 utility on the database file, and use its special dot commands:
.tables will list tables
.schema [tablename] will show the CREATE statement(s) for a table or tables
There are many other useful builtin dot commands -- see the documentation at http://ww...
Best practices for overriding isEqual: and hash
...ive you do
result = prime * result + var
For objects you use 0 for nil and otherwise their hashcode.
result = prime * result + [var hash];
For booleans you use two different values
result = prime * result + ((var)?1231:1237);
Explanation and Attribution
This is not tcurdt's work, and ...
Why is MATLAB so fast in matrix multiplication?
I am making some benchmarks with CUDA, C++, C#, Java, and using MATLAB for verification and matrix generation. When I perform matrix multiplication with MATLAB, 2048x2048 and even bigger matrices are almost instantly multiplied.
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no new variables on left side of :=
......]int{11,12,14}
colon : is used when you perform the short declaration and assignment for the first time as you are doing in your first statement i.e. myArray :=[...]int{12,14,26}.
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Possible Loss of Fraction
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imageUploader: {
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IOCTL Linux device driver [closed]
...space application to send it orders. However, ioctls are not very flexible and tend to get a bit cluttered (dozens of "magic numbers" which just work... or not), and can also be insecure, as you pass a buffer into the kernel - bad handling can break things easily.
An alternative is the sysfs interf...
How Pony (ORM) does its tricks?
Pony ORM does the nice trick of converting a generator expression into SQL. Example:
1 Answer
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Booleans, conditional operators and autoboxing
...ave in common; since null (type "the special null type") can be implicitly converted (widened) to any type, you can consider the special null type to be a "superclass" of any type (class) for the purposes of lub().
– Bert F
Apr 25 '14 at 13:03
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What does the exclamation mark mean in a Haskell declaration?
...s I try to learn Haskell using a real project to drive it. I don't understand what the exclamation mark in front of each argument means and my books didn't seem to mention it.
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Cocoa Core Data efficient way to count entities
...just solved this task with selecting all with NSFetchedResultsController and getting the count of the NSArray ! I am sure this is not the best way...
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