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Android AsyncTask threads limits?
...ery time user logs in to the system, I also use database in the phone. For all those operations (updates, retrieving data from db and etc.) I use async tasks. As up till now I didn't see why I shouldn't use them, but recently I experienced that if I do some operations some of my async tasks simply s...
How to convert int to QString?
...
Then you probably want to work on pre-allocated buffers... but this sounds like a separate question.
– Georg Fritzsche
Apr 6 '17 at 4:45
a...
Is there a float input type in HTML5?
...>
(I'd also set min=0 if it can only be positive)
If you'd prefer to allow any number of decimal places, you can use step="any" (though for currencies, I'd recommend sticking to 0.01). In Chrome & Firefox, the stepper buttons will increment / decrement by 1 when using any. (thanks to Micha...
Why use a prime number in hashCode?
...ly be determined by the least significant entry (the one not multiplied at all). Similar entries will collide. Not good for a hash function.
31 is a large enough prime that the number of buckets is unlikely to be divisible by it (and in fact, modern java HashMap implementations keep the number of b...
Should I prefer pointers or references in member data?
... be null. This can be an advantage, but if the code ever needs changing to allow rebinding or for the member to be null, all uses of the member need to change
unlike pointer members, references can't easily be replaced by smart pointers or iterators as refactoring might require
Whenever a reference ...
Why is there no String.Empty in Java?
...would save on compile time, in fact I think it would be the latter.
Especially considering Strings are immutable, it's not like you can first get an empty String, and perform some operations on it - best to use a StringBuilder (or StringBuffer if you want to be thread-safe) and turn that into a Str...
Difference between Key, Primary Key, Unique Key and Index in MySQL
...would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have t...
CSS text-overflow in a table cell?
...d flexibility. Also, the containing table will need a specific width, typically width: 100%;, and the columns will typically have their width set as percentage of the total width
table {width: 100%;}
td
{
max-width: 0;
overflow: hidden;
text-overflow: ellipsis;
white-space: nowrap;
}
td.column_a...
Javascript array search and remove string?
...
I'm actually updating this thread with a more recent 1-line solution:
let arr = ['A', 'B', 'C'];
arr = arr.filter(e => e !== 'B'); // will return ['A', 'C']
The idea is basically to filter the array by selecting all elements d...
What is the MySQL VARCHAR max size?
...er is subject to the maximum row size (65,535 bytes, which is shared among all columns) and the character set used.
However, note that the limit is lower if you use a multi-byte character set like utf8 or utf8mb4.
Use TEXT types inorder to overcome row size limit.
The four TEXT types are TINY...