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Strings as Primary Keys in SQL Database [closed]
I am not very familiar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
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Build a Basic Python Iterator
...ator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly called at each loop increment. This method raises a...
SQL Server - SELECT FROM stored procedure
... what if, we need to send parameters to mulple stored procedures and combine them into one one big stored procedure? Can view, take parameters, like stored procedures does
– mrN
Aug 18 '11 at 7:14
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Find unique rows in numpy.array
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+1 This is clear, short and pythonic. Unless speed is a real issue, these type of solutions should take preference over the complex, higher voted answers to this question IMO.
– Bill Cheatham
Apr 30 '14 at 13:3...
SQLite select where empty?
...n I select records where some_column is empty?
Empty counts as both NULL and "".
4 Answers
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How to use GROUP BY to concatenate strings in SQL Server?
... or User-Defined Function needed.
Just need to be creative with FOR XML and PATH.
[Note: This solution only works on SQL 2005 and later. Original question didn't specify the version in use.]
CREATE TABLE #YourTable ([ID] INT, [Name] CHAR(1), [Value] INT)
INSERT INTO #YourTable ([ID],[Name],[Va...
Array slices in C#
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Note that only single dimensional and jagged arrays are enumerable, multi dimensional arrays are not.
– Abel
Apr 8 '10 at 9:11
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What is the best way to compare floats for almost-equality in Python?
...nown that comparing floats for equality is a little fiddly due to rounding and precision issues.
15 Answers
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Algorithm to detect intersection of two rectangles?
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The standard method would be to do the separating axis test (do a google search on that).
In short:
Two objects don't intersect if you can find a line that separates the two objects. e.g. the objects / all points of an object ar...
Why is there no SortedList in Java?
In Java there are the SortedSet and SortedMap interfaces. Both belong to the Java Collections framework and provide a sorted way to access the elements.
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