Erlang mnesia qlc example
Mnesia Errors caseclause in QLC query without a case clause. Qualifiers are either filters or generators. Filters are Erlang expressions returning boolean (). Generators have the form Pattern ListExpression, where ListExpression is an expression evaluating to a query handle or a list. Which means we cannot variable assignments within a QLC query.The secret of joy in work is contained in one word excellence. To know how to do something well is to enjoy it. Pearl S. Buck. erlangquestions (at) erlang. org mailing list. erlang mnesia qlc example
An intro to basic Mnesia, a distributed database for Erlang terms. We get into The Godfather's realm and write a transactional system to track friends and services.
Mnesia 1 Mnesia User's Guide Mnesia is a distributed DataBase Management System(DBMS), appropriate for telecommunications applications and other Erlang applications which require continuous operation and exhibit soft realtime properties. 1. 1 Introduction This book describes the Mnesia DataBase Management System (DBMS). Getting Started. A QLC table is created by calling qlc: table2. Usually qlc: table2 is not called directly from the query but through an interface function of some data structure. ErlangOTP includes a few examples of such functions: mnesia: table1, 2, ets: table1, 2, anderlang mnesia qlc example Chapter 2, Getting Started with Mnesia , introduces Mnesia with an example database. Examples are shown of how to start an Erlang session, specify a Mnesia database directory, initialize a database schema, start Mnesia, and create tables. Initial prototyping of record definitions is also discussed.