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Should I be concerned about excess, non-running, Docker containers?
...running are not taking any system resources besides disk space.
It is usually good to clean up after yourself, but if you have a lot of them sitting around it shouldn't slow down performance at all.
If you do notice a slow down when running docker commands with lots of stopped containers, it mig...
The SQL OVER() clause - when and why is it useful?
...ou use a GROUP BY or not
Example: get count per SalesOrderID and count of all
SELECT
SalesOrderID, ProductID, OrderQty
,COUNT(OrderQty) AS 'Count'
,COUNT(*) OVER () AS 'CountAll'
FROM Sales.SalesOrderDetail
WHERE
SalesOrderID IN(43659,43664)
GROUP BY
SalesOrderID, ProductID,...
Appending an element to the end of a list in Scala
...'s because you shouldn't do it (at least with an immutable list).
If you really really need to append an element to the end of a data structure and this data structure really really needs to be a list and this list really really has to be immutable then do eiher this:
(4 :: List(1,2,3).reverse).rev...
What is “(program)” in Chrome debugger’s profiler?
...
(program) is Chrome itself, the root of the tree calling all other code...it's there because the jump from native code to JavaScript, resource loading, etc. has to start somewhere :)
You can see examples of the treeview in the Chrome developer tool docs.
...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...ger numbers, which might cause trouble if you're converting a table. Personally I'd rather have the query error out up front and know that some of my "integers" are screwy (You can also select with E'\\d{6,}$' first to make sure).
– Anthony Briggs
May 5 '17 at ...
Install a Python package into a different directory using pip?
...
Use:
pip install --install-option="--prefix=$PREFIX_PATH" package_name
You might also want to use --ignore-installed to force all dependencies to be reinstalled using this new prefix. You can use --install-option to multiple times to a...
What is the use of the %n format specifier in C?
...f characters printed thus far to an int variable), but so far no one has really given an example of what use it has. Here is one:
int n;
printf("%s: %nFoo\n", "hello", &n);
printf("%*sBar\n", n, "");
will print:
hello: Foo
Bar
with Foo and Bar aligned. (It's trivial to do that with...
Set time to 00:00:00
...present a moment as it lacks any concept of time zone or offset-from-UTC. Calling LocalDateTime.now almost never makes sense. Use ZonedDateTime instead. Otherwise you are ignoring crucial time zone issues. For one thing, some dates in some zones do not start at 00:00!
– Basil B...
Adding two Java 8 streams, or an extra element to a stream
...ream.concat(lhs, Stream.of(rhs));
}
With these two static methods (optionally in combination with static imports), the two examples could be written as follows:
Stream<Foo> stream = concat(stream1, concat(stream2, element));
Stream<Foo> stream = concat(
conca...
Implementing comparison operators via 'tuple' and 'tie', a good idea?
(Note: tuple and tie can be taken from Boost or C++11.)
When writing small structs with only two elements, I sometimes tend to choose a std::pair , as all important stuff is already done for that datatype, like operator< for strict-weak-ordering.
The downsides though are the pretty much us...