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How do I create a parameterized SQL query? Why Should I?
...ple would do this through a server side programming language library, like PHP's PDO or Perl DBI.
For instance, in PDO:
$dbh=pdo_connect(); //you need a connection function, returns a pdo db connection
$sql='insert into squip values(null,?,?)';
$statement=$dbh->prepare($sql);
$data=array('my...
How many String objects will be created when using a plus sign?
...catenating in a loop. E.g. How many string objects does the following code allocate: string s = ""; for (int i = 0; i < n; i++) s += "a";
– Joren
Feb 3 '12 at 20:08
1
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Practical uses of different data structures [closed]
...tworks of communication, data organization etc.
Heap - Dynamic memory allocation in lisp
This is the answer originally posted by RV Pradeep
Some other, less useful links:
Applications are only listed for some data structures
Not application focused, by good summary and relevant
...
Why does .NET foreach loop throw NullRefException when collection is null?
... either return an empty collection — it is a call to constructor, memory allocation, and perhaps a bunch of a code to be executed. Either you could just return «null» → obviously there's only a code to return and a very short code to check is the argument is «null». It's just a performance.
...
How do I prevent node.js from crashing? try-catch doesn't work
From my experience, a php server would throw an exception to the log or to the server end, but node.js just simply crashes. Surrounding my code with a try-catch doesn't work either since everything is done asynchronously. I would like to know what does everyone else do in their production servers.
...
Base64 length calculation?
...ss the point of the original question, which is how much space needs to be allocated to fit the base64 encoding for a given binary string of length n bytes.
The answer is (floor(n / 3) + 1) * 4 + 1
This includes padding and a terminating null character. You may not need the floor call if you are ...
Can we instantiate an abstract class?
...that here: -
Whenever a new class instance is created, memory space is allocated
for it with room for all the instance variables declared in the class
type and all the instance variables declared in each superclass of the
class type, including all the instance variables that may be hidden....
WKWebView not loading local files under iOS 8
...athComponent;
... then start it up like so:
_webServer = [[GCDWebServer alloc] init];
[_webServer addGETHandlerForBasePath:@"/" directoryPath:docRoot indexFilename:@"index.html" cacheAge:3600 allowRangeRequests:YES];
[_webServer startWithPort:port bonjourName:nil];
To stop it:
[_webServer stop...
Location Services not working in iOS 8
...
- (void)startLocationManager
{
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.distanceFilter = kCLDistanceFilterNone; //whenever we move
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager startUpdat...
How are zlib, gzip and zip related? What do they have in common and how are they different?
...educed with compression factor 4
6 - The file is Imploded
7 - Reserved for Tokenizing compression algorithm
8 - The file is Deflated
9 - Enhanced Deflating using Deflate64(TM)
10 - PKWARE Data Compression Library Imploding (old IBM TERSE)
11 - Reserved by PKWARE
12 - File is compressed using BZIP2 a...