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Why use AJAX when WebSockets is available?
...tive games, dynamic media streams, bridging to existing network protocols, etc).
However, there is certainly an overlap in purpose between WebSockets and AJAX/Comet. For example, when the browser wants to be notified of server events (i.e. push) then Comet techniques and WebSockets are certainly bo...
SQL JOIN and different types of JOINs
...Note that a JOIN without any other JOIN keywords (like INNER, OUTER, LEFT, etc) is an INNER JOIN. In other words, JOIN is
a Syntactic sugar for INNER JOIN (see: Difference between JOIN and INNER JOIN).
2. OUTER JOIN :
OUTER JOIN retrieves
Either,
the matched rows from one table and all row...
Image width/height as an attribute or in CSS? [duplicate]
... would have to be redrawn for floated elements, specified padding, margins etc.
Whether to specify in html or css is best judged on individual circumstances. A large number of images of the same size would probably be best served with css, a single image with html. That said, if you are specifying ...
Finding local IP addresses using Python's stdlib
...s won't work always (returns 127.0.0.1 on machines having the hostname in /etc/hosts as 127.0.0.1), a paliative would be what gimel shows, use socket.getfqdn() instead. Of course your machine needs a resolvable hostname.
sha...
Approximate cost to access various caches and main memory?
...es for example).
Additionally, this page has some details on clock cycles etc. The second link served the following numbers:
Core i7 Xeon 5500 Series Data Source Latency (approximate) [Pg. 22]
local L1 CACHE hit, ~4 cycles ( 2.1 - 1.2 ns )
local L...
How to set host_key_checking=false in ansible inventory file?
...al:
Ansible User Guide - Host Key Checking
You can do it either in the /etc/ansible/ansible.cfg or ~/.ansible.cfg file:
[defaults]
host_key_checking = False
Or you can setup and env variable (this might not work on newer ansible versions):
export ANSIBLE_HOST_KEY_CHECKING=False
...
MongoDB mongorestore failure: locale::facet::_S_create_c_locale name not valid
...
this basically helped me. but also had to edit /etc/locale.gen and enable the needed locales (on arch linux)
– Marian Theisen
Jan 28 '14 at 16:27
...
git ignore vim temporary files
... Vim will create successively named swap files (.swp, .swo, etc.), so I use .*.sw* in my .gitignore to hide them all.
– Drew Stephens
May 20 '11 at 1:15
33
...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 13: ordinal not in range(128)
... error related... Using the following command:
grep -r -P '[^\x00-\x7f]' /etc/apache2 /etc/letsencrypt /etc/nginx
Found mine in
/etc/letsencrypt/options-ssl-nginx.conf: # The following CSP directives don't use default-src as
Using shed, I found the offending sequence. It turned out to...
Why does sudo change the PATH?
...d binary folders in
the PATH. Having already added my
requirements to /etc/environment I was
surprised when I got errors about
missing commands when running them
under sudo.....
I tried the following to fix this
without sucess:
Using the "sudo -E" option - did not work. My ...