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Difference between EXISTS and IN in SQL?
...way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match is found
exists ( select * from [table] where ... )
This is most useful where you have if conditional statements, as exists can be a lot ...
Set the selected index of a Dropdown using jQuery
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First of all - that selector is pretty slow. It will scan every DOM element looking for the ids. It will be less of a performance hit if you can assign a class to the element.
$(".myselect")
To answer your question though, there are a few w...
Why is SELECT * considered harmful?
Why is SELECT * bad practice? Wouldn't it mean less code to change if you added a new column you wanted?
15 Answers
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Forward declaring an enum in C++
...ifferent sizes, but I'm fairly sure that data pointers have to round-trip (cast to another data pointer type, then back to the original, need to still work), which implies that all data pointers are the same size.
– Ben Voigt
Mar 9 '10 at 4:53
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Best way to unselect a in jQuery?
What is the best way, using jQuery, to elegantly unselect the option?
15 Answers
15
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Using union and order by clause in mysql
...criteria from a table based on distance for a search on my site.
The first select query returns data related to the exact place search .
The 2nd select query returns data related to distance within 5 kms from the place searched.
The 3rd select query returns data related to distance within 5-15 kms f...
How to get all selected values from ?
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The usual way:
var values = $('#select-meal-type').val();
From the docs:
In the case of <select multiple="multiple"> elements, the .val() method returns an array containing each selected option;
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Get selected value of a dropdown's item using jQuery
How can I get the selected value of a dropdown box using jQuery?
I tried using
30 Answers
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Set selected option of select box
I want to set a option that was selected previously to be displayed on page load. I tried it with the following code:
16 An...
how to use ng-option to set default value of select element
I've seen the documentation of the Angular select directive here: http://docs.angularjs.org/api/ng.directive:select .
I can't figure how to set the default value. This is confusing:
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