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How to use index in select statement?
...tion,
Usually the DB engine should automatically select the index to use based on query execution plans it builds. However, there are some pretty rare cases when you want to force the DB to use a specific index.
To be able to answer your specific question you have to specify the DB you are using....
jQuery checkbox checked state changed event
...
Action taking based on an event (on click event).
$('#my_checkbox').on('click',function(){
$('#my_div').hide();
if(this.checked){
$('#my_div').show();
}
});
Without event taking action based on current state.
$('#my_...
Is there a Java equivalent or methodology for the typedef keyword in C++?
...
The referenced anti-pattern article is based on the assumption that you just want to shorten your typing (which would actually hide the helpful type information). The real use most people want is to disambiguate types and let the compiler do its job for you. See...
How do I create a variable number of variables?
...s that the only difference in each of those lines is a number that changes based on a rule, and decides to use a loop. However, they get stuck on how to dynamically create those variable names, and may try something like this:
for i in range(10):
my_calculator.('button_%d' % i) = tkinter.Button...
Repeat String - Javascript
...;>= 1, pattern += pattern;
}
return result + pattern;
}
It is based on artistoex algorithm.
It is really fast. And the bigger the count, the faster it goes compared with the traditional new Array(count + 1).join(string) approach.
I've only changed 2 things:
replaced pattern = this ...
When would you use the different git merge strategies?
...asis, the resolve strategy works like this: pick one of the possible merge bases, and hope for the best. This is actually not as bad as it sounds. It often turns out that the users have been working on different parts of the code. In that case, Git detects that it's remerging some changes that are a...
optional local variables in rails partial templates: how do I get out of the (defined? foo) mess?
...opying the code from the OP's link (api.rubyonrails.org/classes/ActionView/Base.html) <% if local_assigns.has_key? :headline %> Headline: <%= headline %> <% end %> -- has_key avoids the nil / false situation, and probably can be shortened to one line like the answer here
...
In which order do CSS stylesheets override?
...rt: more specific rules override more general ones. Specificity is defined based on how many IDs, classes, and element names are involved, as well as whether the !important declaration was used. When multiple rules of the same "specificity level" exist, whichever one appears last wins.
...
How do I terminate a thread in C++11?
... advise developer or even require build multithreading applications on the base of cooperative or synchronous thread termination. The reason for this common decisions and advices is that all they are built on the base of the same general multithreading model.
Let's compare multiprocessing and multi...
How to remove all whitespace from a string?
...
## [3] " \t\n\r\v\fx \t\n\r\v\fy \t\n\r\v\f"
## [4] NA
The base R approach: gsub
gsub replaces all instances of a string (fixed = TRUE) or regular expression (fixed = FALSE, the default) with another string. To remove all spaces, use:
gsub(" ", "", x, fixed = TRUE)
## [1] "xy" ...