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Limiting the number of records from mysqldump?
... @Phob: The --where option is basically appended to a query of the form SELECT * from table WHERE , so in this case you get SELECT * from table WHERE 1 limit 1000000. Without the 1, you would have an invalid query. Specifying 1 for a where clause (since 1 is always true) simply selects all reco...
Apple Mach-O Linker Error when compiling for device
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In some case error log window displaying .xctest error, to fix it
-> Select your project
-> Beside this(just before General tab) select your projectTest file from dropdown
-> There is one option (like ProjNameTests)
-> In Host Application, select your project from dropdown only if ...
Rails 4 LIKE query - ActiveRecord adds quotes
...have Movie.where("title ILIKE :s", s: search_string) it gets translated to SELECT 1 AS one FROM "movies" WHERE (title ILIKE 'test') LIMIT $1 by ActiveRecord (Rails 5.1.6) - please notice that there is no percentage symbol after the ILIKE)
– sekmo
Aug 16 '19 at...
Window appears off screen on ubuntu [closed]
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Be sure to have the off-screen window selected (use Alt-Tab or Super-W for example). Then hold Alt+F7 and move the window with the cursor keys until it appears in the viewport.
When this happens to me the hidden window is usually below the screen (I occasionally...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...rows affected (0.02 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM tin3;
+----+------------+
| id | val |
+----+------------+
| 1 | 0000000012 |
| 2 | 0000000007 |
| 4 | 0000000101 |
+----+------------+
3 rows in set (0.00 sec)
mysql>
mysql> SELECT LENGTH(val)...
Floating point vs integer calculations on modern hardware
...tv.tv_usec);
# endif
}
template< typename Type >
void my_test(const char* name) {
Type v = 0;
// Do not use constants or repeating values
// to avoid loop unroll optimizations.
// All values >0 to avoid division by 0
// Perform ten ops/iteration to reduce
// impact of ++i be...
What is the use of Enumerable.Zip extension method in Linq?
...rator merges the corresponding elements of two sequences using a specified selector function.
var letters= new string[] { "A", "B", "C", "D", "E" };
var numbers= new int[] { 1, 2, 3 };
var q = letters.Zip(numbers, (l, n) => l + n.ToString());
foreach (var s in q)
Console.WriteLine(s);
Oupu...
AVD Manager - Cannot Create Android Virtual Device
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You either haven't selected a CPU/ABI target in the dropdown below the target, or you haven't installed a system image. Open your SDK manager and ensure that you've installed ARM EABI v7a System Image under the Android 4.2 section.
...
Parallel.ForEach vs Task.Run and Task.WhenAll
...e that your second example can be shortened to
await Task.WhenAll(strings.Select(s => Task.Run(() => DoSomething(s)));
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
...t z = add(x, y);
sum += z;
}
return sum;
}
int main(int , char* argv[]) {
int result = work(*argv[1], *argv[2]);
return result;
}
and compiled as: g++ -O2 add.cpp main.cpp.
gcc won't inline add()!
That's all, it's that easy to unintendedly create hotspots l...