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Auto-expanding layout with Qt-Designer
...your widget/dialog/window (not the QVBoxLayout, but the parent widget) and select Lay Out -> Lay Out in a Grid from the bottom of the context-menu. The QVBoxLayout should now stretch to fit the window and will resize automatically when the entire window is resized.
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Query to count the number of tables I have in MySQL
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SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'dbName';
Source
This is mine:
USE databasename;
SHOW TABLES;
SELECT FOUND_ROWS();
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Properly escape a double quote in CSV
... Why was this answer ever voted up? The comment about escaping characters was never backed up and the original question doesn't ask about PHP. This only seems to be true for the string delimiter (and only for the chosen delimiter) when a program, such as Open Office, allows you to change...
SQL to find the number of distinct values in a column
I can select all the distinct values in a column in the following ways:
11 Answers
11
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Is Meyers' implementation of the Singleton pattern thread safe?
...ingleton& instance()
{
static bool initialized = false;
static char s[sizeof( Singleton)];
if (!initialized) {
initialized = true;
new( &s) Singleton(); // call placement new on s to construct it
}
return (*(reinterpret_cast<Singleton*>( &s)))...
Why there is no ForEach extension method on IEnumerable?
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Couldn't you just use Select instead of your Apply method? It seems to me that applying an action to each element and yielding it is exactly what Select does. E.g. numbers.Select(n => n*2);
– rasmusvhansen
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Is there any performance gain in indexing a boolean field?
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It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
How to navigate through textfields (Next / Done Buttons)
...m
#import "UITextField+Extended.h"
#import <objc/runtime.h>
static char defaultHashKey;
@implementation UITextField (Extended)
- (UITextField*) nextTextField {
return objc_getAssociatedObject(self, &defaultHashKey);
}
- (void) setNextTextField:(UITextField *)nextTextField{
o...
How to send password securely over HTTP?
...ded using
the RFC2045-MIME variant of Base64, except not limited to 76
char/line.
The authorization method and a space i.e. "Basic " is then
put before the encoded string.
source: Wikipedia: Authorization header
It might seem a bit complicated, but it is not.
There are plenty go...
How to get Top 5 records in SqLite?
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SELECT * FROM Table_Name LIMIT 5;
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