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sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
SET versus SELECT when assigning variables?
What are the differences between the SET and SELECT statements when assigning variables in T-SQL?
4 Answers
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Clear Text Selection with JavaScript
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if (window.getSelection) {
if (window.getSelection().empty) { // Chrome
window.getSelection().empty();
} else if (window.getSelection().removeAllRanges) { // Firefox
window.getSelection().removeAllRanges();
}
} else if (doc...
Vim: faster way to select blocks of text in visual mode
I have been using vim for quite some time and am aware that selecting blocks of text in visual mode is as simple as SHIFT + V and moving the arrow key up or down line-by-line until I reach the end of the block of text that I want selected.
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Rails select helper - Default selected value, how?
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This should do it:
<%= f.select :project_id, @project_select, :selected => params[:pid] %>
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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What is the best way to solve an Objective-C namespace collision?
...uld prefix them with "IBM"; if you work for Microsoft, you could use "MS"; and so on. Sometimes the initials refer to the project, e.g. Adium prefixes classes with "AI" (as there is no company behind it of that you could take the initials). Apple prefixes classes with NS and says this prefix is rese...
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...
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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What are best practices that you use when writing Objective-C and Cocoa? [closed]
I know about the HIG (which is quite handy!), but what programming practices do you use when writing Objective-C, and more specifically when using Cocoa (or CocoaTouch).
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