## 1 Introduction

Mnemosyne is a query language of Mnesia and provides a simple syntax for complex queries.

| QLC (Query List Comprehensions) is another solution for queries to Mnesia, Ets and Dets tables which will be the recommended way to perform queries. QLC belongs to Stdlib and is described there. It is not recommended to use Mnemosyne queries in performance critical applications.

`Mnesia` is a distributed DataBase Management System, utilized for telecommunications applications and other Erlang applications which require continuous operation and soft real-time properties. Mnesia is part of the Open Telecom Platform (OTP), which is a control system platform for building telecommunications applications.

### 1.1 Scope and Purpose

This manual is included as a part of the OTP document set. It describes how to use Mnemosyne queries. Programming constructs are described, and numerous programming examples are included to illustrate the use of Mnemosyne.

### 1.2 Pre-requisites

It is assumed that the reader is familiar with system development principles and database management systems. Readers are also assumed to be familiar with the Erlang programming language in general, and the `Mnesia` application in particular.

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