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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...
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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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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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?
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PHP Get all subdirectories of a given directory
How can I get all sub-directories of a given directory without files, . (current directory) or .. (parent directory)
and then use each directory in a function?
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Git Pull While Ignoring Local Changes?
...it stash
git pull
git stash pop
I don't think it makes any sense to literally ignore the changes, though - half of pull is merge, and it needs to merge the committed versions of content with the versions it fetched.
share
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CROSS JOIN vs INNER JOIN in SQL
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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...
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...
Are C++ enums signed or unsigned?
...integral type is used as the underlying type for an enum, except that it shall not be larger than int, unless some value cannot fit into int or an unsigned int.
In short: you cannot rely on an enum being either signed or unsigned.
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SQL exclude a column using SELECT * [except columnA] FROM tableA?
We all know that to select all columns from a table, we can use
41 Answers
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