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| Erlang Term Storage |
Erlang Term Storage
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.
Quick Start
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.
ETS Demo in IEX
iex(1)> myETSTable = :ets.new(:my_ets_table, [])
#Reference<0.1520230345.550371329.65846>
iex(2)> :ets.insert(myETSTable, {"favoriteWebSite", "freeCodeCamp"})
true
iex(3)> :ets.insert(myETSTable, {"favoriteProgrammingLanguage", "Elixir"})
true
iex(4)> :ets.i(myETSTable)
<1 > {<<"favoriteProgrammingLanguage">>,<<"Elixir">>}
<2 > {<<"favoriteWebSite">>,<<"freeCodeCamp">>}
EOT (q)uit (p)Digits (k)ill /Regexp -->
Persistence
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.
Use cases
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.