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Why does Oracle 9i treat an empty string as NULL?
... spot on. The most confusing situations arise when '' is being implicitely converted to a VARCHAR2, such as cast('' as char(1)) is null which is... surprisingly TRUE
– sehe
Jul 19 '13 at 15:17
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Python CSV error: line contains NULL byte
...
Converting the encoding of the source file from UTF-16 to UTF-8 solve my problem.
How to convert a file to utf-8 in Python?
import codecs
BLOCKSIZE = 1048576 # or some other, desired size in bytes
with codecs.open(sourceFil...
How to add leading zeros?
...
Note that sprintf converts numeric to string (character).
– aL3xa
Apr 28 '11 at 8:54
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Is it better to call ToList() or ToArray() in LINQ queries?
...lare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
16...
Usage of protocols as array types and function parameters in swift
.... Such protocols use Self or associatedtype keywords in their definitions (and Equatable is one of them).
In some cases it's possible to use a type-erased wrapper to make your collection homomorphic. Below is an example.
// This protocol doesn't provide polymorphism over the types which implement ...
Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
...
The explanation comes from Agner Fog in Optimizing software in C++ and it reduces to how data is accessed and stored in the cache.
For terms and detailed info, see the wiki entry on caching, I'm gonna narrow it down here.
A cache is organized in sets and lines. At a time, only one set is u...
Is there a performance difference between a for loop and a for-each loop?
... The for-each loop, introduced in
release 1.5, gets rid of the clutter
and the opportunity for error by
hiding the iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (...
Setting Short Value Java
... There are suffixes for other types as well: d/D makes a double and f/F makes a float!
– Joachim Sauer
Feb 19 '10 at 8:48
6
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Create an enum with string values
...at way it will return the string value whenever accessed and not just when converting toString().
– John
Feb 28 '14 at 23:37
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builtins.TypeError: must be str, not bytes
I've converted my scripts from Python 2.7 to 3.2, and I have a bug.
2 Answers
2
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