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How many database indexes is too many?
...ntless since it doesn't add anything in terms of looking the data up. The more unique the values in a column, the more it will benefit from an index.
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Difference between VARCHAR and TEXT in MySQL [duplicate]
...space where c is the length of the stored string
can be part of an index
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TEXT has a fixed max size of 2¹⁶-1 = 65535 characters.
VARCHAR has a variable max size M up to M = 2¹⁶-1.
So you cannot choose the size of TEXT but you can for a VARCHAR.
The other difference is, that you...
Executors.newCachedThreadPool() versus Executors.newFixedThreadPool()
...s crash due to long-time CPU waiting. So I think newFixedThreadPool can be more secure in this kind of scenario. Also this post clarifies the most outstanding differences between them.
– Hearen
May 10 '18 at 3:46
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What is the difference between dict.items() and dict.iteritems() in Python2?
... @Stew the change is described in PEP 3106 and there is a bit more in what's new in python 3.0
– Tadhg McDonald-Jensen
Apr 22 '16 at 18:57
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Recursion or Iteration?
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It is possible that recursion will be more expensive, depending on if the recursive function is tail recursive (the last line is recursive call). Tail recursion should be recognized by the compiler and optimized to its iterative counterpart (while maintaining th...
Can I extend a class using more than 1 class in PHP?
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Html.Partial vs Html.RenderPartial & Html.Action vs Html.RenderAction
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Html.Partial() was created to have a more fluent syntax with Razor. As @Vlad said, Html.RenderPartial() is more efficient.
– Tsahi Asher
Apr 10 '14 at 11:25
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How to merge two arrays in JavaScript and de-duplicate items
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SQL “select where not in subquery” returns no results
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These articles in my blog describe the differences between the methods in more detail:
NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: SQL Server
NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: PostgreSQL
NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: Oracle
NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS...
How do I disable a Pylint warning?
I'm trying to disable warning C0321 ("more than one statement on a single line" -- I often put if statements with short single-line results on the same line), in Pylint 0.21.1 (if it matters: astng 0.20.1, common 0.50.3, Python 2.6.6 (r266:84292, Sep 15 2010, 16:22:56)).
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