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Surrogate vs. natural/business keys [closed]
...er question is what to use for a logical primary key. They are both essentially just non-null unique index constraints.
– dkretz
Feb 12 '09 at 22:11
1
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How to change the CHARACTER SET (and COLLATION) throughout a database?
...
Do you really need to use "ALTER TABLE <table_name> MODIFY <column_name> ...". According to dev.mysql.com/doc/refman/5.5/en/alter-table.html it seems "ALTER TABLE <table_name> CONVERT TO CHARACTER SET ..." also chan...
How to uninstall the “Microsoft Advertising SDK” Visual Studio extension?
...or me) is the "Microsoft Advertising SDK for Windows 8.1". I like to uninstall extensions I don't need, but this one won't allow me. if I hover the (enabled!) button it says in a tooltip:
...
What is the role of the bias in neural networks? [closed]
...
I think that biases are almost always helpful. In effect, a bias value allows you to shift the activation function to the left or right, which may be critical for successful learning.
It might help to look at a simple example. Consider this 1-input, 1-output network that has no bias:
The ou...
Turning a Comma Separated string into individual rows
...F(String, 1, CHARINDEX(',', String + ','), '')
FROM Testdata
UNION all
SELECT
SomeID,
OtherID,
LEFT(String, CHARINDEX(',', String + ',') - 1),
STUFF(String, 1, CHARINDEX(',', String + ','), '')
FROM tmp
WHERE
String > ''
)
SELECT
S...
Which is faster: while(1) or while(2)?
...
mov rbp, rsp
.seh_setframe rbp, 0
sub rsp, 32
.seh_stackalloc 32
.seh_endprologue
call __main
.L2:
jmp .L2
.seh_endproc
.ident "GCC: (tdm64-2) 4.8.1"
With -O1:
.file "main.c"
.intel_syntax noprefix
.def __main; .scl 2; .type 32; .end...
How to remove trailing whitespaces with sed?
...
hm. its also buggy in the sense that it will remove all trailing "t"s :)
– Good Person
Aug 1 '14 at 2:30
2
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Python __str__ versus __unicode__
...onfusing, but in 2.x we're stuck with them for compatibility reasons. Generally, you should put all your string formatting in __unicode__(), and create a stub __str__() method:
def __str__(self):
return unicode(self).encode('utf-8')
In 3.0, str contains characters, so the same methods are nam...
Method Resolution Order (MRO) in new-style classes?
...ject'>)
with A forced to come in resolution order only once and after all of its subclasses, so that overrides (i.e., C's override of member x) actually work sensibly.
It's one of the reasons that old-style classes should be avoided: multiple inheritance with "diamond-like" patterns just doesn...
mongodb/mongoose findMany - find all documents with IDs listed in array
I have an array of _ids and I want to get all docs accordingly, what's the best way to do it ?
5 Answers
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