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CHECK constraint in MySQL is not working
...ySQL Reference Manual says:
The CHECK clause is parsed but ignored by all storage engines.
Try a trigger...
mysql> delimiter //
mysql> CREATE TRIGGER trig_sd_check BEFORE INSERT ON Customer
-> FOR EACH ROW
-> BEGIN
-> IF NEW.SD<0 THEN
-> SET NEW.SD=0;...
How to make lists contain only distinct element in Python? [duplicate]
...ictionary keys, which might be okay for some purposes, but doesn't support indexing for example.
– Mark
Dec 3 '16 at 11:57
...
In a Git repository, how to properly rename a directory?
... force
git mv -f oldfolder newfolder
Don't forget to add the changes to index & commit them after renaming with git mv.
3. Renaming foldername to folderName on case insensitive file systems
Simple renaming with a normal mv command(not git mv) won’t get recognized as a filechange from git....
Backbone.js get and set nested object attribute
...Yes it does, if you look at the API there is an example like //You can use index notation to fetch from arrays console.log(model.get('otherSpies.0.name')) //'Lana'
– tawheed
Nov 13 '13 at 13:30
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boost Composite keys - C/C++ - 清泛网 - 专注C/C++及内核技术
...n two or more fields of a given table The analogous concept in Boost MultiIndex is Composite keys
In relational databases, composite keys depend on two or more fields of a given table. The analogous concept in Boost.MultiIndex is modeled by means of composite_key, as shown in the example:
...
How to take column-slices of dataframe in pandas
...precated. Use .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz...
What do (lambda) function closures capture?
...he way.
If you wanted, you could write a small class that uses your array-indexing syntax:
class Adders(object):
def __getitem__(self, item):
return lambda a: a + item
adders = Adders()
adders[1](3)
share
...
Why array implements IList?
...
Because an array allows fast access by index, and IList/IList<T> is are the only collection interfaces that support this. So perhaps your real question is "Why is there no interface for constant collections with indexers?" And to that I have no answer.
Ther...
Get child node index
...tensions such as jQuery, etc.), is there a way to determine a child node's index inside of its parent node without iterating over and comparing all children nodes?
...
count (non-blank) lines-of-code in bash
... Just habit. I read pipelines from left to right, which means I usually start with cat, then action, action, action, etc. Clearly, the end result is the same.
– Michael Cramer
Sep 24 '08 at 14:06
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