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MySQL foreign key constraints, cascade delete
...#2 (blue):
DELETE FROM categories WHERE (id = 2);
the DBMS will look at all the tables which have a foreign key pointing at the 'categories' table, and delete the records where the matching id is 2. Since we only defined the foreign key relationship in products_categories, you end up with this ta...
What is the difference between related SQLite data-types like INT, INTEGER, SMALLINT and TINYINT?
When creating a table in SQLite3, I get confused when confronted with all the possible datatypes which imply similar contents, so could anyone tell me the difference between the following data-types?
...
How exactly does the python any() function work?
...st of some items. If it contained [0, False, '', 0.0, [], {}, None] (which all have boolean values of False) then any(lst) would be False. If lst also contained any of the following [-1, True, "X", 0.00001] (all of which evaluate to True) then any(lst) would be True.
In the code you posted, x > ...
How to configure postgresql for the first time?
I have just installed postgresql and I specified password x during installation.
When I try to do createdb and specify any password I get the message:
...
What do commas and spaces in multiple classes mean in CSS?
..._12 .grid_6,
.container_16 .grid_8 {
width: 460px;
}
That says "make all .grid_6's within .container_12's and all .grid_8's within .container_16's 460 pixels wide." So both of the following will render the same:
<div class="container_12">
<div class="grid_6">460px Wide</div&g...
Nginx location priority
...th the "=" prefix that match the query exactly. If found, searching stops.
All remaining directives with conventional strings. If this match used the "^~" prefix, searching stops.
Regular expressions, in the order they are defined in the configuration file.
If #3 yielded a match, that result is used...
Store JSON object in data attribute in HTML jQuery
...in the text just use $('#myElement').data('key',jsonObject);
it won't actually be stored in the html, but if you're using jquery.data, all that is abstracted anyway.
To get the JSON back don't parse it, just call:
var getBackMyJSON = $('#myElement').data('key');
If you are getting [Object Objec...
Why is git push gerrit HEAD:refs/for/master used instead of git push origin master
...o the staging area (in the diagram, "Pending Changes"). Gerrit doesn't actually have a branch called <BRANCH>; it lies to the git client.
Internally, Gerrit has its own implementation for the Git and SSH stacks. This allows it to provide the "magical" refs/for/<BRANCH> refs.
When ...
In HTML5, is the localStorage object isolated per page/domain?
... separate (and they're both separate from http://example.com) as those are all different hosts. Similarly, http://example.com:80 and http://example.com:8080 and https://example.com are all different origins.
There is no mechanism built into web storage that allows one origin to access the storage o...
'await' works, but calling task.Result hangs/deadlocks
...g to schedule its continuation onto a thread that is being blocked by the call to Result.
In this case, your SynchronizationContext is the one used by NUnit to execute async void test methods. I would try using async Task test methods instead.
...