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ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
...get started with JDBC, you need to be sure that you can connect to the database using SQL*Plus. If you're not familiar with SQL*Plus, it's a command-line tool for connecting to Oracle databases that has been a standard part of Oracle for a long time and it is included with Oracle XE.
When connecti...
How to implement an abstract class in ruby?
...s (Symbol or Array) list of method names to be treated as
# abstract base methods
#
def self.abstract_methods(*methods)
methods.each do |method_name|
define_method method_name do
raise NotImplementedError, 'This is an abstract base method. Implement in your sub...
What's the UIScrollView contentInset property for?
... Sorry to piggyback on this, I can move it its own question, but based on this, what actually happens if you set each contentInset value to 0 other than the contentHeight for example? Does that force the whole scrollview to be the height you set it to?
– jakev
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What is the most ridiculous pessimization you've seen? [closed]
...bing 16 bits from RAM was quicker than grabbing 32 bits.
I had to write a demo program to show that grabbing 32-bit values on a 32-bit system was faster than grabbing 16-bit values, and explain that to grab a 16-bit value the CPU had to make a 32-bit wide memory access and then mask out or shift th...
LINQ Select Distinct with Anonymous Types
...for Distinct()
public override int GetHashCode()
{
return base.GetHashCode();
}
public bool Equals(CommonClass other)
{
if (other == null) return false;
return [equality test];
}
}
...
Best practices for SQL varchar column length [closed]
...n UK are usually between 1-35 characters. If you decide to make it varchar(64), you're not really going to hurt anything... unless you're storing this guy's family name that's said to be up to 666 characters long. In that case, maybe varchar(1028) makes more sense.
And in case it's helpful, here's ...
Get IP address of visitors using Flask for Python
...re users can log on and download files, using the Flask micro-framework (based on Werkzeug ) which uses Python (2.6 in my case).
...
Coding Conventions - Naming Enums
...
In our codebase; we typically declare enums in the class that they belong to.
So for your Fruit example, We would have a Fruit class, and inside that an Enum called Fruits.
Referencing it in the code looks like this: Fruit.Fruits.App...
What is the difference between NaN and None?
...n reason to use NaN (over None) is that it can be stored with numpy's float64 dtype, rather than the less efficient object dtype, see NA type promotions.
# without forcing dtype it changes None to NaN!
s_bad = pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype...
Simple Log to File example for django 1.3+
...
Based partially on the logging config suggested by rh0dium and some more research I did myself, I started assembling an example Django project with nice logging defaults – fail-nicely-django.
Sample logfile output:
2016-0...