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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...
Python function attributes - uses and abuses [closed]
...ciated data together:
#!/usr/bin/env python
SW_DELTA = 0
SW_MARK = 1
SW_BASE = 2
def stopwatch():
import time
def _sw( action = SW_DELTA ):
if action == SW_DELTA:
return time.time() - _sw._time
elif action == SW_MARK:
_sw._time = time.time()
retur...
Is inject the same thing as reduce in ruby?
...
i like to separate them based on how it's used, obviously just for semantics. if its a proc (&:+), reduce, if it's a block, inject
– TheRealMrCrowley
Jan 8 '18 at 20:12
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What does [:] mean?
...nce.
Next:
x[:] = obj
Is a way to set the items (it calls __setitem__) based on obj.
and, I think you can probably guess what:
del x[:]
calls ;-).
You can also pass different slices:
x[1:4]
constructs slice(1,4,None)
x[::-1]
constructs slice(None,None,-1) and so forth. Further readin...
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 ...
CSS: bolding some text without changing its container's size
...over { text-shadow: -0.06ex 0 black, 0.06ex 0 black; }
}
There is a live demo with a slider to play with various grades on the Mozilla Variable Fonts Guide. Google's Introduction to variable fonts on the web has an animated GIF demonstrating a toggle between a high grade and no grade:
...
How is __eq__ handled in Python and in what order?
...
base on this answer and accompanied comments , this just left me more confused than before.
– Sajuuk
May 14 '19 at 8:48
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Expand Python Search Path to Other Source
I have just joined a project with a rather large existing code base. We develop in linux and do not use and IDE. We run through the command line. I'm trying to figure out how to get python to search for the right path when I run project modules. For instance, when I run something like:
...
pretty-print JSON using JavaScript
...ring, you had a normal object. JSON is always a string. It's just a string-based representation of a Javascript object.
– Clonkex
Jan 3 '18 at 2:53
add a comment
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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...