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How to add a primary key to a MySQL table?
... Column
If you want to add a primary key constraint to an existing column all of the previously listed syntax will fail.
To add a primary key constraint to an existing column use the form:
ALTER TABLE `goods`
MODIFY COLUMN `id` INT(10) UNSIGNED PRIMARY KEY AUTO_INCREMENT;
...
Difference between Python's Generators and Iterators
...ry generator is an iterator, but not vice versa. A generator is built by calling a function that has one or more yield expressions (yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph's definition of an iterator.
You may want to use a custom iterator, ra...
How dangerous is it to compare floating point values?
...
First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on...
Scala vs. Groovy vs. Clojure [closed]
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Groovy is a dynamically typed language, whose syntax is very close to Java, with a number of syntax improvements that allow for lighter code and less boilerplate. It can run through an interpreter as well as being compiled, which makes it good ...
How do I commit case-sensitive only filename changes in Git?
... listing finds makefile when git expects Makefile, git will assume it is really the same file, and continue to remember it as Makefile.
The default is false, except git-clone(1) or git-init(1) will probe and set core.ignorecase true if appropriate when the repository is created.
Case-insensitive fi...
Inheritance and Overriding __init__ in python
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The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo,...
$apply vs $digest in directive testing
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scope.$digest() will fire watchers on the current scope, and on all of its children, too. scope.$apply will evaluate passed function and run $rootScope.$digest().
The first one is faster, as it needs to evaluate watchers for current scope and its children. The second one is slower, as it...
Breaking out of a nested loop
...using goto is any worse than the normal use of something like break (after all they're both just unconditional branches to a label, it's just that with break the label is implicit).
– Greg Beech
Nov 28 '08 at 0:07
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Entity Framework 4 vs NHibernate [closed]
...ork 4 and NHibernate. We can say that today NHibernate is the leader among all .NET ORMs, but can we expect Entity Framework 4 to displace NHibernate from this position. I think if Microsoft has really injected very good features in EF4 it can give good competition to NHibernate as it has Visual Stu...
How do I copy directories recursively with gulp?
...c( [ files ], { "base" : "." }) can be used in the structure above to copy all the directories recursively.
If, like me, you may forget this then try:
gulp.copy=function(src,dest){
return gulp.src(src, {base:"."})
.pipe(gulp.dest(dest));
};
...