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SQL left join vs multiple tables on FROM line?
...ave multiple employees.
Ok, so now you want to do the following:
List all the companies, and include all their departments, and all their employees. Note that some companies don't have any departments yet, but make sure you include them as well. Make sure you only retrieve departments that have...
All but last element of Ruby array
...re_ext.rb file with little extensions like this. Some libraries are practically all extensions like this: ActiveSupport for example.
– rfunduk
Oct 22 '09 at 0:30
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Why does using an Underscore character in a LIKE filter give me all the results?
...t end with 'abc'.
In your case you have searched by '%_%'. This will give all the rows with that column having one or more characters, that means any characters, as its value. This is why you are getting all the rows even though there is no _ in your column values.
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How can I propagate exceptions between threads?
We have a function which a single thread calls into (we name this the main thread). Within the body of the function we spawn multiple worker threads to do CPU intensive work, wait for all threads to finish, then return the result on the main thread.
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How to fix error “Updating Maven Project”. Unsupported IClasspathEntry kind=4?
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It might help to remove manually from the .classpath file all the classpathentry with the kind attribute set to var.
– Puigcerber
Aug 21 '12 at 9:29
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SQL query return data from multiple tables
...I-89 syntax (and if you are used to 89, may seem much less intuitive - but all I can say is to try it) as it is much easier to understand when the queries start getting more complex. Why use it? Is there a performance gain? The short answer is no, but it is easier to read once you get used to it. It...
How does python numpy.where() work?
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How do they achieve internally that you are able to pass something like x > 5 into a method?
The short answer is that they don't.
Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolea...
Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewe...
Remove all but numbers from NSString
...thesis and hyphens as some phone numbers are formatted. How would I remove all characters except numbers from the string?
2...
CROSS JOIN vs INNER JOIN in SQL
...---------------------------------x
2. CROSS JOIN
Cross join selects the all the rows from the first table and all the rows from second table and shows as Cartesian product ie, with all possibilities
Consider we need to find all the teachers in the school and students irrespective of class teacher...