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How do I use prepared statements in SQlite in Android?
... Below are some examples:
Create a table
String sql = "CREATE TABLE table_name (column_1 INTEGER PRIMARY KEY, column_2 TEXT)";
SQLiteStatement stmt = db.compileStatement(sql);
stmt.execute();
The execute() method does not return a value so it is appropriate to use with CREATE and DROP but not in...
What is the difference between “px”, “dip”, “dp” and “sp”?
...
@android_developer (5 comments above) dp does not have the exact same physical length. (Although it is close.) See @Fraggle's comment about bucketing. What this means is that 48dp will be roughly 8mm (0.3 inch), but it may vary up to...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...e
### HEADER ###
LOCKFILE="/var/lock/`basename $0`"
LOCKFD=99
# PRIVATE
_lock() { flock -$1 $LOCKFD; }
_no_more_locking() { _lock u; _lock xn && rm -f $LOCKFILE; }
_prepare_locking() { eval "exec $LOCKFD>\"$LOCKFILE\""; trap _no_more_locking EXIT; }
# ON START
_prepare_l...
Why do we use __init__ in Python classes?
...ical piece of understanding: the difference between a class and an object. __init__ doesn't initialize a class, it initializes an instance of a class or an object. Each dog has colour, but dogs as a class don't. Each dog has four or fewer feet, but the class of dogs doesn't. The class is a concept o...
Python: Why is functools.partial necessary?
...mbda:
>>> pickle.dumps(partial(int))
'cfunctools\npartial\np0\n(c__builtin__\nint\np1\ntp2\nRp3\n(g1\n(tNNtp4\nb.'
>>> pickle.dumps(lambda x: int(x))
Traceback (most recent call last):
File "<ipython-input-11-e32d5a050739>", line 1, in <module>
pickle.dumps(lambd...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...maticReferenceCounting.html#ownership.spelling.property
assign implies __unsafe_unretained ownership.
copy implies __strong ownership, as well as the usual behavior of copy
semantics on the setter.
retain implies __strong ownership.
strong implies __strong ownership.
unsafe...
How to [recursively] Zip a directory in PHP?
...ion to be loaded.
function Zip($source, $destination)
{
if (!extension_loaded('zip') || !file_exists($source)) {
return false;
}
$zip = new ZipArchive();
if (!$zip->open($destination, ZIPARCHIVE::CREATE)) {
return false;
}
$source = str_replace('\\', '/'...
Python Dictionary Comprehension
...a subclass of dict which works somewhat like a defaultdict if you override __missing__:
>>> class KeyDict(dict):
... def __missing__(self, key):
... #self[key] = key # Maybe add this also?
... return key
...
>>> d = KeyDict()
>>> d[1]
1
>>> d[2]
...
urlencode vs rawurlencode?
...php)
Returns a string in which all non-alphanumeric characters except -_.~ have been replaced with a percent (%) sign followed by two hex digits. This is the encoding described in » RFC 3986 for protecting literal characters from being interpreted as special URL delimiters, and for protecting U...