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How can I clear the SQL Server query cache?
...CKPOINT;
GO
DBCC DROPCLEANBUFFERS;
GO
From the linked article:
If all of the performance testing is conducted in SQL Server the best approach may be to issue a CHECKPOINT and then issue the DBCC DROPCLEANBUFFERS command. Although the CHECKPOINT process is an automatic internal system proce...
When to use cla(), clf() or close() for clearing a plot in matplotlib?
...
They all do different things, since matplotlib uses a hierarchical order in which a figure window contains a figure which may consist of many axes. Additionally, there are functions from the pyplot interface and there are methods ...
What is the difference between CascadeType.REMOVE and orphanRemoval in JPA?
...ove
Marking a reference field with CascadeType.REMOVE (or CascadeType.ALL,
which includes REMOVE) indicates that remove operations should be
cascaded automatically to entity objects that are referenced by that
field (multiple entity objects can be referenced by a collection
field):
@En...
Python's equivalent of && (logical-and) in an if-statement
... different name in Python.
The logical operators && and || are actually called and and or.
Likewise the logical negation operator ! is called not.
So you could just write:
if len(a) % 2 == 0 and len(b) % 2 == 0:
or even:
if not (len(a) % 2 or len(b) % 2):
Some additional information (...
Proper way to declare custom exceptions in modern Python?
...tionError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = errors
That way you could pass dict of error me...
How to “warm-up” Entity Framework? When does it get “cold”?
... help increase performance. However with EF5 it isn't necessary to compile all your queries since EF will auto-compile queries itself. The only problem is that these queries can get lost when the cache is swept. So you still want to hold references to your own compiled queries for those that are occ...
Simple explanation of clojure protocols
...eployed, separately type checked. We want them to be type-safe. [Note: not all of these make sense in all languages. But, for example, the goal to have them type-safe makes sense even in a language like Clojure. Just because we can't statically check type-safety doesn't mean that we want our code to...
Android Task Affinity Explanation
...ayer stack of activities, and two of them were the same activity. Popping all 5 off the stack will create the phenomenon where you will be interacting with two different versions of the same activity and can be quite confusing.
Users don't usually think in terms of a rigid stack of activities. ...
Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
Java to Clojure rewrite
...ble state and develop pure (side-effect free) functions. You probably know all this already :-)
Anyway, this philosophy tends to lead towards something of a "bottom up" development style where you focus the initial efforts on building the right set of tools to solve your problem, then finally plug ...