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What is the default initialization of an array in Java?
...unt!!
elementData[size++] = e;
return true;
}
public void add(int index, E element) {
rangeCheckForAdd(index);
ensureCapacityInternal(size + 1); // Increments modCount!!
System.arraycopy(elementData, index, elementData, index + 1,size - index);
elementData[index] = element;...
How to implement a many-to-many relationship in PostgreSQL?
...on CREATE TABLE in the manual.
Primary keys are implemented with a unique index on the key columns, that makes queries with conditions on the PK column(s) fast. However, the sequence of key columns is relevant in multicolumn keys. Since the PK on bill_product is on (bill_id, product_id) in my examp...
Apache Prefork vs Worker MPM
...he earlier, threadsafe model. Worker is multi-threaded, and event supports php-mpm which is supposed to be a better system for handling threads and requests.
However, your results may vary, based on configuration. I've seen a lot of instability in php-mpm and not any speed improvements. An aggress...
How to count the number of set bits in a 32-bit integer?
...a table-lookup for 4 bits at a time of each byte in parallel. (The 4 bits index a 16 entry table held in a vector register).
On Intel CPUs, the hardware 64bit popcnt instruction can outperform an SSSE3 PSHUFB bit-parallel implementation by about a factor of 2, but only if your compiler gets it just...
Reusable library to get human readable version of file size?
...ps, using log2 to determine the size order which doubles as a shift and an index into the suffix list:
from math import log2
_suffixes = ['bytes', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']
def file_size(size):
# determine binary order in steps of size 10
# (coerce to int, /...
Use ASP.NET MVC validation with jquery ajax?
...var errorResponse = data.responseJSON;
$.each(errorResponse, function (index, value) {
// Element highlight
var element = $(form).find('#' + value.key);
element = element[0];
highLightError(element, 'input-validation-error');
// Error message
var ...
Replace all non-alphanumeric characters in a string
... as a word character (don't know why): docs.python.org/3.6/library/re.html#index-32
– JHS
Dec 23 '18 at 1:32
You don't...
uncaught syntaxerror unexpected token U JSON
...et, "JSON.parse: unexpected character". I'm returning the json data from a php file and the returning json string is valid. I checked it with http://jsonlint.com/ . Any help would be appreciated... Thanks.
...
What does multicore assembly language look like?
...atomic v8.1 load modify store instructions: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0801g/alc1476202791033.html
WFE / SVE: WFE instruction handling in ARM
What exactly is std::atomic?
Tested in Ubuntu 19.04 amd64 and with QEMU aarch64 user mode.
...
How can I alter a primary key constraint using SQL syntax?
...
Performance wise there is no point to keep non clustered indexes during this as they will get re-updated on drop and create.
If it is a big data set you should consider renaming the table (if possible , any security settings on it?), re-creating an empty table with the correct keys...