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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...P COLUMN column_name1, DROP COLUMN column_name2;
Be aware
DROP COLUMN does not physically remove the data for some DBMS. E.g. for MS SQL. For fixed length types (int, numeric, float, datetime, uniqueidentifier etc) the space is consumed even for records added after the columns were dropped. To ...
Focus Next Element In Tab Index
...e DOM than visually in the browser. Just picking the next tabbable element does not work when you change the order of elements using flexbox.
– Haneev
May 12 '17 at 14:22
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How to find the lowest common ancestor of two nodes in any binary tree?
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That does the job if the parent pointer is given. The nodes in the tree are as the structure I gave in my question - just the left/right child pointers, no parent pointer. Is there any O(log(n)) solution if there is no parent poin...
How do I read the first line of a file using cat?
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Does head read the entire file and cut it, or does it read only the 1 line?
– CMCDragonkai
May 1 '15 at 2:53
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Remove vertical padding from horizontal ProgressBar
...rnKappelHansen It is device dependent. Galaxy S6 and a margin top of -6dp does not work as desired.
– Muhammad Abdul-Rahim
Oct 13 '15 at 14:41
1
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How to apply CSS to iframe?
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Edit: This does not work cross domain unless the appropriate CORS header is set.
There are two different things here: the style of the iframe block and the style of the page embedded in the iframe. You can set the style of the iframe b...
How to properly override clone method?
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@KarlRichter I've read their answer. It does not say it's a bad idea, other than that Cloneable in general is a broken idea, as explained in Effective Java. The OP already expressed that they have to use Cloneable. So I have no idea how else my answer could be impr...
Python memoising/deferred lookup property decorator
...because it avoids sticking extra attributes on objects, and once activated does not waste time checking for attribute presence, etc.:
import functools
class lazy_property(object):
'''
meant to be used for lazy evaluation of an object attribute.
property should represent non-mutable dat...
Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...nd the results come spilling out.
From my reading of the docs, iterator() does nothing more than bypass QuerySet's internal caching mechanisms. I think it might make sense for it to a do a one-by-one thing, but that would conversely require ten-million individual hits on your database. Maybe not ...
Is there a way to get the git root directory in one command?
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This is what hg root does. It prints out the top-level directory of your checked out repository. It doesn't switch you to it (and it couldn't, in fact, do so because of how the whole concept of current directory and your shell interact).
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