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What are the best practices for using a GUID as a primary key, specifically regarding performance?
...have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, but...
Combining “LIKE” and “IN” for SQL Server [duplicate]
Is it possible to combine LIKE and IN in a SQL Server-Query?
6 Answers
6
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Big O of JavaScript arrays
Arrays in JavaScript are very easy to modify by adding and removing items. It somewhat masks the fact that most languages arrays are fixed-size, and require complex operations to resize. It seems that JavaScript makes it easy to write poorly performing array code. This leads to the question:
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What is the usefulness of PUT and DELETE HTTP request methods?
... origin server. If the Request-URI does not point to an existing resource, and that URI is capable of being defined as a new resource by the requesting user agent, the origin server can create the resource with that URI …
For the full specification visit:
http://www.w3.org/Protocols/rfc2616/rf...
What is the most efficient/elegant way to parse a flat table into a tree?
..., 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.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive que...
What is the difference between join and merge in Pandas?
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I always use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l ...
Should an Enum start with a 0 or a 1?
...ag enum values of zero unless the value represents "all flags are cleared" and is named appropriately, as prescribed by the next guideline.
✔️ DO name the zero value of flag enums None. For a flag enum, the value must always mean "all flags are cleared."
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How to check if an object is a list or tuple (but not string)?
...es I stumbled upon bugs where a function passes a str object by mistake, and the target function does for x in lst assuming that lst is actually a list or tuple .
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How can we programmatically detect which iOS version is device running on? [duplicate]
I want to check if the user is running the app on iOS less than 5.0 and display a label in the app.
10 Answers
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Why doesn't java.util.Set have get(int index)?
... itself. Two of the three commonly used implementations of List (ArrayList and Vector) are random-access, but that does not make random access a property of Lists.
– Michael Myers♦
Aug 5 '12 at 4:29
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