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How do I force Postgres to use a particular index?
...of why and what you can do instead can be found here. The reasons are basically that it's a performance hack that tends to cause more problems later down the line as your data changes, whereas PostgreSQL's optimizer can re-evaluate the plan based on the statistics. In other words, what might be a go...
When to use IMG vs. CSS background-image?
...ng icon. This ensures that the meaning of the image can be communicated in all user-agents, including screen readers.
Pragmatic uses of IMG
Use IMG plus alt attribute if the image
is part of the content such as a logo or diagram or person (real person, not stock photo people).
—sanchothefat...
How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
What's the idiomatic syntax for prepending to a short python list?
... @MattM. If you insert at the front of a list, python has to move all the other items one space forwards, lists can't "make space at the front". collections.deque (double ended queue) has support for "making space at the front" and is much faster in this case.
– fejfo
...
get size of json object
... check the size i.e. like that:
var data = {one : 1, two : 2, three : 3};
_.size(data);
//=> 3
_.keys(data);
//=> ["one", "two", "three"]
_.keys(data).length;
//=> 3
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What should be in my .gitignore for an Android Studio project?
...kbox and mark the "use default gradle wrapper (recommended)" radio button. All paths are now relative as @George suggested.
Updated answer according to @128KB attached source and @Skela suggestions
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Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...roblem . After a long search I found a comment which had been ignored by all users pointing to the missing lib. Now, many months later, the comment has been changed to an answer. However, when I answered this question by msyself I intended to help other people by directly providing the solution. T...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
How to use dashes in HTML-5 data-* attributes in ASP.NET MVC
...an underscore.
For example:
@Html.TextBoxFor(vm => vm.City, new { data_bind = "foo" })
will render this in MVC 3:
<input data-bind="foo" id="City" name="City" type="text" value="" />
If you're still using an older version of MVC, you can mimic what MVC 3 is doing by creating this sta...
Why have header files and .cpp files? [closed]
...dencies so that code that uses the header doesn't necessarily need to know all the details of the implementation and any other classes/headers needed only for that. This will reduce compilation times and also the amount of recompilation needed when something in the implementation changes.
It's not ...