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What's the difference between TRUNCATE and DELETE in SQL
...cle
If you use the REUSE STORAGE clause then the data segments are not de-allocated, which can be marginally more efficient if the table is to be reloaded with data. The high water mark is reset.
Row scope
Delete can be used to remove all rows or only a subset of rows. Truncate removes all rows...
What is the difference between pluck and collect in Rails?
... Because it will retrieve all the columns from user table in the database, allocates the memory for each attributes (including the attributes which you will never use)
NOTE: pluck does not return ActiveRecord_Relation of the user
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Why use String.Format? [duplicate]
...the exact size of the destination string is known ahead of time and can be allocated immediately and each character copied only once.
– csauve
Jan 12 '11 at 17:44
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Why should a function have only one exit-point? [closed]
...ns require more code since you have to do proper clean up of memory spaces allocated for variables. Consider a scenario where function allocates variables (resources) and getting out of the function early and without proper clean up would result in resource leaks. In addition, constructing clean-up ...
How many parameters are too many? [closed]
...umber of CPU registers, because anymore and the compiler will be forced to allocate them on the stack.
– Michaelangel007
Mar 31 '16 at 14:10
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Difference between core and processor
... @Nrj, if you run one single-threaded application, it will be allocated to a single core, and activate only a single HW thread on it. That thread will be able to utilize 100% of that core as there is no other thread running along with it. If you activate another application it will usua...
Try catch statements in C
... a number of down sides (but is a fun mental exercise):
It will not free allocated memory as there are no deconstructors being called.
You can't have more than 1 try/catch in a scope (no nesting)
You can't actually throw exceptions or other data like in C++
Not thread safe at all
You are setting u...
Return all enumerables with yield return at once; without looping through
...rhead if all the client really needs is to enumerate through it, since you allocate the data structures for all elements in advance. Also, if you delegate to another method that's returning a sequence, then capturing it as a collection involves extra copying, and you do not know how many items (and ...
Convert ArrayList to String[] array [duplicate]
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According to Joshua Bloch in Effective Java, preallocating the array harms performance. Provide a zero-length array instead. stockList.toArray(new String[0])
– Crashh
Mar 10 '18 at 3:20
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What are file descriptors, explained in simple terms?
....h) opened by default on behalf of shell when the program starts.
FD's are allocated in the sequential order, meaning the lowest possible unallocated integer value.
FD's for a particular process can be seen in /proc/$pid/fd (on Unix based systems).
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