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Create an index on a huge MySQL production table without table locking
...If your using a version greater than 5.1 indices are created while the database is online. So not to worry you won't interrupt production system use."
This is ****FALSE**** (at least for MyISAM / InnoDB tables, which is what 99.999% of people out there use. Clustered Edition is different.)
Doing...
Swift - Split string over multiple lines
...ed compile-time optimization, even at -Onone. ," adcdownload.apple.com/WWDC_2015/Xcode_7_beta/…
– Kostiantyn Koval
Jul 31 '15 at 18:19
2
...
Best way to assert for numpy.array equality?
...some unit-tests for my app, and I need to compare two arrays. Since array.__eq__ returns a new array (so TestCase.assertEqual fails), what is the best way to assert for equality?
...
Django South - table already exists
...
Although the table "myapp_tablename" already exists error stop raising
after I did ./manage.py migrate myapp --fake, the DatabaseError shows
no such column: myapp_mymodel.added_field.
Got exactly the same problem!
1.Firstly check the migration...
Why can't I define a default constructor for a struct in .NET?
...ublic struct Tempo
{
const double DefaultBpm = 120;
private double _bpm; // this field must not be modified other than with its property.
public double BeatsPerMinute
{
get => _bpm + DefaultBpm;
set => _bpm = value - DefaultBpm;
}
}
This is different than...
Which letter of the English alphabet takes up most pixels?
I am trying to do some dynamic programming based on the number of characters in a sentence. Which letter of the English alphabet takes up the most pixels on the screen?
...
Python pandas: fill a dataframe row by row
... I see. So the loc attribute of the data frame defines a special __setitem__ that does the magic I suppose.
– xApple
Jun 13 '13 at 16:24
...
Is a view faster than a simple query?
...t is materialized immediately and persisted in physical storage in the database, saving the overhead of performing this costly operation at execution time.
Second, these indexed views can work even when they are not directly referenced by another query as the optimizer will use them in place of a ...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
Print string to text file
...
text_file = open("Output.txt", "w")
text_file.write("Purchase Amount: %s" % TotalAmount)
text_file.close()
If you use a context manager, the file is closed automatically for you
with open("Output.txt", "w") as text_file:
t...