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Types in MySQL: BigInt(20) vs Int(20)
...---+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+------------------+------+-----+---------+-------+
| id | int(20) unsigned | YES | | NULL | |
+-------+------------------+------+-----+---------+-------+
1 row in set (0,00 sec)
mysql> IN...
How do I declare a 2d array in C++ using new?
...algorithms to do it. And the allocator "pads" each of your row arrays with extra bytes for bookkeeping and alignment. That extra space costs...well...extra space. The deallocator will also take extra time when you go to deallocate the matrix, painstakingly free-ing up each individual row allocation....
What are the mechanics of short string optimization in libc++?
This answer gives a nice high-level overview of short string optimization (SSO). However, I would like to know in more detail how it works in practice, specifically in the libc++ implementation:
...
PHP substring extraction. Get the string before the first '/' or the whole string
I am trying to extract a substring. I need some help with doing it in PHP.
15 Answers
...
How do I use pagination with Django class based generic ListViews?
... I have been doing this, but the problem I find, is when I do extra processing on objects in the queryset, it applys them to all of the results in the database. So for a query that returns 100 objects, but shows only ten objects per page, the extra processing will be done on 100 objects...
Benefits of header-only libraries
...is because the Windows API has functions which use either Unicode or ASCII strings and macros/defines which automagically use the correct types based on the project's Unicode settings. If you pass a string across the library boundary that is the wrong type then things break at runtime. Or you may fi...
What are all the differences between src and data-src attributes?
...r" to this question; src must be included. You use data- attributes to add extra data for a scripting language (like JavaScript) to leverage.
– Tieson T.
Mar 10 '13 at 7:53
ad...
Referring to the null object in Python
...Empty()
>>> empty==None
True
But then it also works on the empty string
>>> empty==''
True
And yet
>>> ''==None
False
>>> empty is None
False
Case 2: Using None as a boolean
The following two tests
if value:
# Do something
if not value:
# Do something
...
Should IBOutlets be strong or weak under ARC?
... Is there such a thing as a redundant retain? If there's an extra retain, that will cause it to not be counted properly, and therefore won't be freed as soon as it could be since there's an extra retain on its retain count.
– karlbecker_com
Feb 2...
sqlite alter table add MULTIPLE columns in a single statement
...und for adding multiple columns using the benefit of transactions in SQL.
String alterTableQuery = "ALTER TABLE " + TABLE_NAME + " ADD COLUMN ";
List<String> newColumns = ..// Your new columns
db.beginTransaction();
for (String column : newColumns){
db.execSQL(alterTableQuery + column + ...