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How do I use prepared statements in SQlite in Android?
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I use prepared statements in Android all the time, it's quite simple :
SQLiteDatabase db = dbHelper.getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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How do I achieve the theoretical maximum of 4 FLOPs per cycle?
... while (i < 1000){
// Here's the meat - the part that really matters.
r0 = _mm_mul_pd(r0,rC);
r1 = _mm_add_pd(r1,rD);
r2 = _mm_mul_pd(r2,rE);
r3 = _mm_sub_pd(r3,rF);
r4 = _mm_mul_pd(r4,rC);
r5 = _mm_add_pd(r5...
Rename Files and Directories (Add Prefix)
I would like to add prefix on all folders and directories.
10 Answers
10
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What new capabilities do user-defined literals add to C++?
C++11 introduces user-defined literals which will allow the introduction of new literal syntax based on existing literals ( int , hex , string , float ) so that any type will be able to have a literal presentation.
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Should import statements always be at the top of a module?
...t that's only paid once.
Putting the imports within a function will cause calls to that function to take longer.
So if you care about efficiency, put the imports at the top. Only move them into a function if your profiling shows that would help (you did profile to see where best to improve perform...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...
In a django model custom save() method, how should you identify a new object?
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Not all models have an id attribute, i.e. a model extending another through a models.OneToOneField(OtherModel, primary_key=True). I think you need to use self.pk
– AJP
Apr 9 '13 at 10:21
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Bash continuation lines
... like a single string which crosses lines, while indenting but not getting all those spaces, one approach you can try is to ditch the continuation line and use variables:
$ a="continuation"
$ b="lines"
$ echo $a$b
continuationlines
This will allow you to have cleanly indented code at the expense ...
How do I get a PHP class constructor to call its parent's parent's constructor?
I need to have a class constructor in PHP call its parent's parent's (grandparent?) constructor without calling the parent constructor.
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Determine project root from a running node.js application
...uire.main === module
Because module provides a filename property (normally equivalent to __filename), the entry point of the current application can be obtained by checking require.main.filename.
So if you want the base directory for your app, you can do:
var path = require('path');
var appD...