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What is the difference between std::array and std::vector? When do you use one over other? [duplicat
...inter to an array; e.g., C library routines. (As an aside, std::vector<char> buf(8192); is a great way to allocate a local buffer for calls to read/write or similar without directly invoking new.)
That said, the lack of that extra level of indirection, plus the compile-time constant size, ca...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
PHP passing $_GET in linux command prompt
...RL in single quotes, as the ? and & in the query portion are shell metacharacters (single char wildcard + "run this command in the background").
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Select mySQL based only on month and year
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SELECT * FROM projects WHERE YEAR(Date) = 2011 AND MONTH(Date) = 5
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Get records with max value for each group of grouped SQL results
...
There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
Postgres manually alter sequence
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The parentheses are misplaced:
SELECT setval('payments_id_seq', 21, true); # next value will be 22
Otherwise you're calling setval with a single argument, while it requires two or three.
...
IIS7 Permissions Overview - ApplicationPoolIdentity
...eplace this text below if it is named differently)
Open Windows Explorer
Select a file or directory.
Right click the file and select "Properties"
Select the "Security" tab
Click the "Edit" and then "Add" button
Click the "Locations" button and make sure you select the local machine. (Not the Windo...
Run PostgreSQL queries from the command line
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psql -U username -d mydatabase -c 'SELECT * FROM mytable'
If you're new to postgresql and unfamiliar with using the command line tool psql then there is some confusing behaviour you should be aware of when you've entered an interactive session.
For example, ...
Get a list of checked checkboxes in a div using jQuery
I want to get a list of names of checkboxes that are selected in a div with certain id. How would I do that using jQuery?
8...
How can I run MongoDB as a Windows service?
...he following error: Cannot open MongoDB service
on computer '.'.
At line:1 char:1
+ Start-Service MongoDB
+ ~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : OpenError: (System.ServiceProcess.ServiceController:ServiceController) [Start-Service],
ServiceCommandException
+ FullyQualifiedError...