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How does database indexing work? [closed]
Given that indexing is so important as your data set increases in size, can someone explain how indexing works at a database-agnostic level?
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Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
What are the differences between PRIMARY, UNIQUE, INDEX and FULLTEXT when creating MySQL tables?
3 Answers
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Accessing the index in 'for' loops?
How do I access the index in a for loop like the following?
20 Answers
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What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...rious mapping commands. What that means is that if you do:
:map j gg
:map Q j
:noremap W j
j will be mapped to gg. Q will also be mapped to gg, because j will be expanded for the recursive mapping. W will be mapped to j (and not to gg) because j will not be expanded for the non-recursive mapping....
Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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What is normalized UTF-8 all about?
...input.
Canonical normalization comes in 2 forms: NFD and NFC. The two are equivalent in the sense that one can convert between these two forms without loss. Comparing two strings under NFC will always give the same result as comparing them under NFD.
NFD
NFD has the characters fully expanded out. Th...
sql primary key and index
...base set as the primary key. If I query off the ID often do I also need to index it? Or does it being a primary key mean it's already indexed?
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Should I index a bit field in SQL Server?
I remember reading at one point that indexing a field with low cardinality (a low number of distinct values) is not really worth doing. I admit I don't know enough about how indexes work to understand why that is.
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What does the git index contain EXACTLY?
What does the Git index exactly contain, and what command can I use to view the content of the index?
5 Answers
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How to see indexes for a database or table in MySQL?
How do I see if my database has any indexes on it?
9 Answers
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