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Implementing IDisposable correctly
...uld have any unmanaged resources to be freed you should include Finalizer calling Dispose(false), that will allow GC to call Finalizer when doing garbage collection (in case Dispose was not called yet) and properly free unmanaged resources.
– mariozski
May 17 '...
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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Queries vs. Filters
...erefore faster than queries. Have a look here too. Let's say a query is usually something that the users type and pretty much unpredictable, while filters help users narrowing down the search results , for example using facets.
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Coding Practices which enable the compiler/optimizer to make a faster program
...act.
Expect to be disappointed and to have to work very hard indeed for small performance improvements. Modern compilers for mature languages such as Fortran and C are very, very good. If you read an account of a 'trick' to get better performance out of code, bear in mind that the compiler writer...
How to allocate aligned memory only using the standard library?
...
Original answer
{
void *mem = malloc(1024+16);
void *ptr = ((char *)mem+16) & ~ 0x0F;
memset_16aligned(ptr, 0, 1024);
free(mem);
}
Fixed answer
{
void *mem = malloc(1024+15);
void *ptr = ((uintptr_t)mem+15) & ~ (uintptr_t)0x0...
Access an arbitrary element in a dictionary in Python
...
for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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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...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...
Setting the correct encoding when piping stdout in Python
...you must encode it yourself.
A rule of thumb is: Always use Unicode internally. Decode what you receive, and encode what you send.
# -*- coding: utf-8 -*-
print u"åäö".encode('utf-8')
Another didactic example is a Python program to convert between ISO-8859-1 and UTF-8, making everything upper...
Django South - table already exists
...
Got it, thanks. It's actually migrate and not schemamigration, but your answer got me in the right direction.
– Steve
Jun 22 '10 at 7:17
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