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Understanding Python's “is” operator
...ually wrong! Thanks for pointing that out @martijn-pieters ! I should know by now never to post code without testing it! >>> x=1.0; y=1.0 >>> x is y True >>> x=1.0 >>> y=1.0 >>> x is y False
– Magnus Lyckå
Sep 26 '...
Pandas get topmost n records within each group
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Did you try df.groupby('id').head(2)
Ouput generated:
>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that...
Android: remove notification from notification bar
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what about those notification which are created by system?
– Zaid Mirza
Mar 21 '19 at 11:30
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Rails :include vs. :joins
...was changed to use multiple queries in some circumstances. This blog post by Fabio Akita has some good information on the change (see the section entitled "Optimized Eager Loading").
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improv...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
I am getting this error when I GetById() on an entity and then set the collection of child entities to my new list which comes from the MVC view.
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Oracle SQL: Update a table with data from another table
...ltiple times for some/all records (not clean). Secondly: there is no order by clause so this will occur in an unpredictable manner (i.e. last value in unordered data wins). Thirdly: It will be much slower. Assuming the outcome of the for loop was intended, the original subselect could have been rewr...
Finding the id of a parent div using Jquery
...).parents(parentsSelector) will select all parents of the elements matched by selector that match the parent selector. http://docs.jquery.com/Traversing/parents#expr
Thus: $(selector).parents('div:eq(0)'); will match the first parent div of the elements matched by selector.
You should have a look at...
Foreign key constraint may cause cycles or multiple cascade paths?
...mple cases. Fact remains, SQL Server doesn't even try, plays it ultra safe by disallowing more than one path and at least it tells you so.
Microsoft themselves advises the use of triggers instead of FK constraints.
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How do I kill all the processes in Mysql “show processlist”?
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You need to kill them one by one, MySQL does not have any massive kill command. You can script it in any language, for example in PHP you can use something like:
$result = mysql_query("SHOW FULL PROCESSLIST");
while ($row=mysql_fetch_array($result)) ...
Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
Is there any way in which I can clean a database in SQl Server 2005 by dropping all the tables and deleting stored procedures, triggers, constraints and all the dependencies in one SQL statement?
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