

Ask HN: When Did Indexes and Query Planners Become a Part of a Database? - dedalus

I wanted to see if anyone here knew how they got integrated in the modern database system and what were the adoption challenges and maturity issues before we all now take then for granted.
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greenyoda
Indexes are very old; they predate database systems. For example, old IBM
mainframe operating systems had indexed sequential files (ISAM)[1] in the
1960s. Early databases - the ones based on hierarchical and network data
models that preceded relational databases - all had indexes.

Query optimization dates all the way back to IBM's System R, a research
database that was the first implementation of SQL.[2] The third reference in
the Wikipedia article[3] is the paper on query optimization published by the
IBM team in 1979. Query optimization was needed to make the performance of
relational databases competitive with the older databases that existed at the
time, since complex queries across joined tables could be very inefficient if
implemented naively (the largest mainframes in those days only had a few
megabytes of memory).

[1] [https://en.wikipedia.org/wiki/ISAM](https://en.wikipedia.org/wiki/ISAM)

[2]
[https://en.wikipedia.org/wiki/IBM_System_R](https://en.wikipedia.org/wiki/IBM_System_R)

[3]
[https://en.wikipedia.org/wiki/Query_optimization#References](https://en.wikipedia.org/wiki/Query_optimization#References)

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ksherlock
Some of us have been using indexes since 1896 or so.
[http://en.wikipedia.org/wiki/Edge-
notched_card](http://en.wikipedia.org/wiki/Edge-notched_card)

