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How to delete from multiple tables in MySQL?
...ding deletes can cause no more trouble than delete on its own. We already know that pa is a proper child of p due to the id/pet_id mapping.
– paxdiablo
Jul 26 '10 at 3:24
...
How does facebook, gmail send the real time notification?
...e number of requests, and how often you have to send them. You effectively now have an event framework that allows the server to 'fire' events.
Behind this, in terms of the actual content returned from those polls, it's a JSON response, with what appears to be a list of events, and info about them....
Python - When to use file vs open
...he moment. They've had a sort of strange relationship, but file() is going now, so there's no need to worry anymore.
The following is from the Python 2.6 docs. [bracket stuff] added by me.
When opening a file, it’s preferable to use open() instead of invoking this [file()] constructor directl...
What column type/length should I use for storing a Bcrypt hashed password in a Database?
...define the column as CHAR(60) CHARACTER SET latin1 COLLATE latin1_bin, you now get the advantages of accurate string comparison without needing a binary column.
– Ben
Feb 25 '14 at 16:01
...
What is BSON and exactly how is it different from JSON?
...and binary that aren't supported in JSON.
In practice, you don't have to know much about BSON when working with MongoDB, you just need to use the native types of your language and the supplied types (e.g. ObjectId) of its driver when constructing documents and they will be mapped into the appropria...
How to smooth a curve in the right way?
...
@TimKuipers I tried this but get an error because now the x parameter has only size 2 (the scipy function does not seem to look "deeper" to see that this is actually a tuple of arrays each of size m, for m data points)
– Chris K
Apr 16 ...
Random date in C#
...he adviced - put the variable out of the method and put all in class. Plus now the time is random too. Here is the result.
class RandomDateTime
{
DateTime start;
Random gen;
int range;
public RandomDateTime()
{
start = new DateTime(1995, 1, 1);
gen = new Random(...
ORDER BY the IN value list
... it has to be spread: in mySQL this can be done much simpler, but I don't know if it works in other SQL.
SELECT * FROM `comments`
WHERE `comments`.`id` IN ('12','5','3','17')
ORDER BY FIELD(`comments`.`id`,'12','5','3','17')
...
Multiple commands in an alias for bash
...ias lock='gnome-screensaver && gnome-screensaver-command --lock'
Now the second command will not even be attempted unless the first one is successful. A better description of short-circuit evaluation is described in this SO question.
...
initializer_list and move semantics
... const initializer_list at the compiler's discretion, so the user doesn't know whether to expect a const or mutable result from begin and end. But that's just my gut feeling, probably there's a good reason I'm wrong.
Update: I've written an ISO proposal for initializer_list support of move-only typ...