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How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...
What is Bit Masking?
...
the b to indicate binary literal is not supported by all compilers, correct?
– Ungeheuer
May 8 '17 at 23:37
...
Why are unnamed namespaces used and what are their benefits?
...ng directive already took place.
This means you can have free functions called (for example) help that can exist in multiple translation units, and they won't clash at link time. The effect is almost identical to using the static keyword used in C which you can put in in the declaration of identif...
How to print third column to last column?
... Note that this only works if the delimiter is exactly the same between all columns... For example, you can't use cut with a delimiter like \d+. (That I know of.)
– Zach Wily
Jan 13 '10 at 21:11
...
How to send an email with Gmail as provider using Python?
...smtp.gmail.com:587')
server.ehlo()
server.starttls()
Also you should really create From:, To: and Subject: message headers, separated from the message body by a blank line and use CRLF as EOL markers.
E.g.
msg = "\r\n".join([
"From: user_me@gmail.com",
"To: user_you@gmail.com",
"Subject:...
C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...
How to printf “unsigned long” in C?
...here it could print a minus sign when the format specifier was %lu. Technically it's undefined behavior but in reality the variable has an unpredictable value that gets passed to printf which printf then interprets as unsigned. I'm guessing bodacydo's original problem was flow reaching an incorrect ...
Convert a Scala list to a tuple?
...e of Scala sequence using the +: syntax. Also, don't forget to add a catch-all
– ig-dev
Jun 19 '19 at 8:33
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Mapping over values in a python dictionary
..., f(kv[1])), my_dictionary.iteritems()))
but that's not that readable, really.
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