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updating table rows in postgres using subquery
...ery.customer,
address=subquery.address,
partn=subquery.partn
FROM (SELECT address_id, customer, address, partn
FROM /* big hairy SQL */ ...) AS subquery
WHERE dummy.address_id=subquery.address_id;
This syntax is not standard SQL, but it is much more convenient for this type of query...
In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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fo...
Why does Popen.communicate() return b'hi\n' instead of 'hi'?
...ing of the bytes you received from the subprocess, you can use decode() to convert them into a printable str:
>>> print(b'hi\n'.decode('ascii'))
hi
Of course, this specific example only works if you actually are receiving ASCII from the subprocess. If it's not ASCII, you'll get an excep...
OSX - How to auto Close Terminal window after the “exit” command executed.
...
in Terminal.app
Preferences > Profiles > (Select a Profile) > Shell.
on 'When the shell exits' chosen 'Close the window'
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How to properly check if std::function is empty in C++11?
... an empty lambda doesn't really make sense. Behind the scenes the compiler converts a lambda expression into a struct (or class) definition, with the variables you capture stored as data members of this struct. A public function call operator is also defined, which is what allows you to invoke the l...
Difference between passing array and array pointer into function in C
...tialize an array, an expression that has type ‘‘array of type’’ is
converted to an expression with type ‘‘pointer to type’’ that points to the initial element of
the array object and is not an lvalue. If the array object has register storage class, the
behavior is undefined.
Given ...
IntelliJ does not show project folders
...next button which takes you to the Content root. Find your root folder and select it
Click the "ok" button
Ignore any warning that says the name is already in use
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Make xargs execute the command once for each line of input
...: space.txt: No such file or directory
A better solution is to use tr to convert newlines to null (\0) characters, and then use the xargs -0 argument. Here's an example:
echo "file with space.txt" | tr '\n' '\0' | xargs -0 ls
file with space.txt
If you then need to limit the number of calls yo...
How to empty a redis database?
...
$ redis-cli then select database. I am selecting 0 > select 0 and delete all keys of db 0 > FLUSHDB
– sagar junnarkar
May 5 '15 at 17:41
...
Angular ng-repeat Error “Duplicates in a repeater are not allowed.”
...cause I mistakenly set the ng-model the same as the ng-repeat array:
<select ng-model="list_views">
<option ng-selected="{{view == config.list_view}}"
ng-repeat="view in list_views"
value="{{view}}">
{{view}}
</option>
</select>
Inste...