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MySQL, update multiple tables with one query
...ookID is very important, without it The Books table update would happen to all rows and not only for the row with the specified id. Some lessons are learned the hard way, this one was learned in the terrifing way.
– nheimann1
Mar 24 '15 at 15:06
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How to read and write INI file with Python3?
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The standard ConfigParser normally requires access via config['section_name']['key'], which is no fun. A little modification can deliver attribute access:
class AttrDict(dict):
def __init__(self, *args, **kwargs):
super(AttrDict, self).__init...
How to detect if a function is called as constructor?
...oking at the ECMAScript 3rd edition spec, the steps taken when new x() is called are essentially:
Create a new object
Assign its internal [[Prototype]] property to the prototype property of x
Call x as normal, passing it the new object as this
If the call to x returned an object, return it, otherw...
How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
JavaScript: how to change form action attribute value based on selection?
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Simple and easy in javascipt
<script>
document.getElementById("selectsearch").addEventListener("change", function(){
var get_form = document.getElementById("search-form") // get form
get_form.action = '/search/' + this.value; // assign val...
ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6.
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mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
What does `:_*` (colon underscore star) do in Scala?
...tes: MetaData, scope: NamespaceBinding,
child: Node*)
which is called as
new Elem(prefix, label, attributes, scope,
child1, child2, ... childN)
but here there is only a sequence, not child1, child2, etc. so this allows the result sequence to be used as the input to the constru...
REST, HTTP DELETE and parameters
...ete=true make sense if this were a program's API? If someone was writing a script to delete this resource, would you want to force them to specify force_delete=true to actually delete the resource?
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