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SQL JOIN vs IN performance?
I have a case where using a JOIN or an IN will give me the correct results... Which typically has better performance and why? How much does it depend on what database server you are running? (FYI I am using MSSQL)
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Check if multiple strings exist in another string
How can I check if any of the strings in an array exists in another string?
15 Answers
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in_array() and multidimensional array
I use in_array() to check whether a value exists in an array like below,
22 Answers
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How does the “this” keyword work?
...ear explanation of what the this keyword is and how it is correctly (and incorrectly) used in JavaScript on the Stack Overflow site.
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Why is there no xrange function in Python3?
Recently I started using Python3 and it's lack of xrange hurts.
6 Answers
6
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#pragma mark in Swift?
In Objective C, I can use #pragma mark to mark sections of my code in the symbol navigator. Since this is a C preprocessor command, it's not available in Swift. Is there a stand-in for this in Swift, or do I have to use ugly comments?
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How to retrieve an element from a set without removing it?
Suppose the following:
12 Answers
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NULL values inside NOT IN clause
...t different records counts for what I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could us...
Python: Why is functools.partial necessary?
...oes functools.partial offer that you can't get through lambdas?
Not much in terms of extra functionality (but, see later) – and, readability is in the eye of the beholder.
Most people who are familiar with functional programming languages (those in the Lisp/Scheme families in particular) appear ...
What are the differences between B trees and B+ trees?
In a b-tree you can store both keys and data in the internal and leaf nodes , but in a b+ tree you have to store the data in the leaf nodes only .
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