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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
Public Fields versus Automatic Properties
...variables vs. properties, so if you rely on reflection, it's easier to use all properties.
You can't databind against a variable.
Changing a variable to a property is a breaking change. For example:
TryGetTitle(out book.Title); // requires a variable
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JavaScript: replace last occurrence of text in a string
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Well, if the string really ends with the pattern, you could do this:
str = str.replace(new RegExp(list[i] + '$'), 'finish');
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Convert JavaScript String to be all lower case?
How can I convert a JavaScript string value to be in all lower case letters?
14 Answers
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How to save all the variables in the current python session?
I want to save all the variables in my current python environment. It seems one option is to use the 'pickle' module. However, I don't want to do this for 2 reasons:
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
Get all object attributes in Python? [duplicate]
Is there a way to get all attributes/methods/fields/etc. of an object in Python?
4 Answers
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How does __proto__ differ from constructor.prototype?
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I've been trying to wrap my head around this recently and finally came up with this "map" that I think sheds full light over the matter
http://i.stack.imgur.com/KFzI3.png
I know I'm not the first one making this up but it was more interesting figuring it out that finding it :-). An...
Solving “Who owns the Zebra” programmatically?
...ution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swede English".split()
pets = "birds dog cats horse zebra".sp...
Creating a div element in jQuery [duplicate]
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@Ricki - no, use double-quotes for all attributes. Single quotes do not produce valid XHTML, although most browsers will tolerate it.
– halfer
Oct 22 '11 at 12:21
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