34 lines
1.8 KiB
Markdown
34 lines
1.8 KiB
Markdown
---
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title: Erlang Term Storage
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---
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## Erlang Term Storage
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Erlang Term Storage, normally abreviated as ETS, is an in-memory database built into OTP, its accessible within Elixir, and is a powerful alternative to solutions like Redis when your application runs on a single node.
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## Quick Start
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To create an ETS table you first need to initalize a table `tableName = :ets.new(:table_otp_name, [])`, once you have initalized a table you can: insert data, lookup values, delete data, and more.
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### ETS Demo in IEX
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```elixir
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iex(1)> myETSTable = :ets.new(:my_ets_table, [])
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#Reference<0.1520230345.550371329.65846>
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iex(2)> :ets.insert(myETSTable, {"favoriteWebSite", "freeCodeCamp"})
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true
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iex(3)> :ets.insert(myETSTable, {"favoriteProgrammingLanguage", "Elixir"})
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true
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iex(4)> :ets.i(myETSTable)
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<1 > {<<"favoriteProgrammingLanguage">>,<<"Elixir">>}
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<2 > {<<"favoriteWebSite">>,<<"freeCodeCamp">>}
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EOT (q)uit (p)Digits (k)ill /Regexp -->
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```
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## Persistence
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ETS Tables are not persistent and are destroyed once the process which owns it terminates. If you would like to store data persistently a traditional database and/or file-based storage is recommended.
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## Use cases
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ETS Tables are commonly used for caching data in the application, for example account data fetched from a database may be stored in an ETS Table to reduce the amount of queries to the database. Another use case is for rate limiting use of features in a web application - ETS's fast read and write speed make it great for this. ETS Tables are a powerful tool for developing highly concurrant web applications at the lowest possible hardware cost.
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#### More Information:
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* [elixir-lang.org | Erlang Libraries (ETS)](https://elixir-lang.org/getting-started/erlang-libraries.html#erlang-term-storage)
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* [erlang.org | ETS](http://erlang.org/doc/man/ets.html)
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