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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 + ...
Is the pImpl idiom really used in practice?
...ss, I would consider caution because all those benefits come at a cost: an extra level of indirection is required in order to access the implementation methods.
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Logging Clientside JavaScript Errors on Server [closed]
...u can also encrypt a token that includes the user's ID, IP, a small random string (to foil known-plaintext attacks if your encryption algorithm is fast but weak), and a timestamp and include that as a JS variable in the page. This can then be submitted with the error report and checked before allow...
Using numpy to build an array of all combinations of two arrays
...
There is bug in this implementation. For arrays of strings for example: arrays[0].dtype = "|S3" and arrays[1].dtype = "|S5". So there is a need in finding the longest string in input and use its type in out = np.zeros([n, len(arrays)], dtype=dtype)
– nor...
Visual Studio 2010 IntelliSense doesn't select a default value - it just marks it
...rue. But you still have to press period to bring up the member's list. One extra step :(
– Tomas Beblar
Jan 5 '16 at 18:36
2
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What are “named tuples” in Python?
...
from typing import NamedTuple
class ANamedTuple(NamedTuple):
"""a docstring"""
foo: int
bar: str
baz: list
The above is the same as the below, except the above additionally has type annotations and a docstring. The below is available in Python 2+:
>>> from collections i...
How can I get the current date and time in UTC or GMT in Java?
...stance of Calendar which uses the local timezone, or possibly using Date.toString() which also uses the local timezone, or a SimpleDateFormat instance, which, by default, also uses local timezone.
If this isn't the problem, please post some sample code.
I would, however, recommend that you use Jod...
Why should I use Deque over Stack?
...et or SortedMap).
We may use the preferred style of declaring like Set<String> set = new HashSet<String>();see reasons here.
But Stack class: 1) don't have its own interface; 2) is a subclass of Vector class - which is based on resizable array; so where is linked list implementation o...
Are there other whitespace codes like   for half-spaces, em-spaces, en-spaces etc useful in HTML
...g space : &#160; or &nbsp;
narrow no-break space : &#8239; (no character reference available)
en space : &#8194; or &ensp;
em space : &#8195; or &emsp;
3-per-em space : &#8196; or &emsp13;
4-per-em space : &#8197; or &emsp14;
6-per-em space : &#8198; ...
Finding Key associated with max Value in a Java Map
...s with maximum value
public class NewClass4 {
public static void main(String[] args)
{
HashMap<Integer,Integer>map=new HashMap<Integer, Integer>();
map.put(1, 50);
map.put(2, 60);
map.put(3, 30);
map.put(4, 60);
map.put(5, 60);
...