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What are the implications of using “!important” in CSS? [duplicate]
...portant:
Specificity is one of the main forces at work when the browser decides how CSS affects the page. The more specific a selector is, the more importance is added to it. This usually coincides with how often the selected element occurs. For example:
button {
color: black;
}
button.highl...
Git diff says subproject is dirty
... For me, I had to go into each dirty submodule and run git clean -id.
– GDP2
Nov 13 '17 at 15:45
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What is the best way to implement nested dictionaries?
...is the best way to implement nested dictionaries in Python?
This is a bad idea, don't do it. Instead, use a regular dictionary and use dict.setdefault where apropos, so when keys are missing under normal usage you get the expected KeyError. If you insist on getting this behavior, here's how to shoo...
Is it possible to use the SELECT INTO clause with UNION [ALL]?
...When we select all records it gives error as- "The ORDER BY clause is invalid in views, inline functions, derived tables, subqueries, and common table expressions, unless TOP or FOR XML is also specified. ". Please give some solution.
– ShaileshDev
Mar 21 '17 a...
How to list containers in Docker
...
To list all running and stopped containers, showing only their container id
docker ps -aq
To remove all containers that are NOT running
docker rm `docker ps -aq -f status=exited`
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Adding 'serial' to existing column in Postgres
... have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
...
Python str vs unicode types
...t; print 'àèìòù'.replace('\xa8', '')
à�ìòù
What before was valid UTF-8, isn't anymore. Using a unicode string you cannot operate in such a way that the resulting string isn't valid unicode text.
You can remove a code point, replace a code point with a different code point etc. but you c...
jQuery Click fires twice when clicking on label
...checked: jQuery('input').prop('checked', true);
– David Sinclair
Sep 5 '14 at 16:57
7
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What is cardinality in MySQL?
...s per the Wikipedia article linked to by Kami.
Why it is important to consider is that it affects indexing strategy. There will be little point indexing a low cardinality column with only 2 possible values as the index will not be selective enough to be used.
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Using DISTINCT and COUNT together in a MySQL Query
...
use
SELECT COUNT(DISTINCT productId) from table_name WHERE keyword='$keyword'
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