Key / Value Database Is A Type Of Nosql Database

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1. Introduction 1.1 Executive Summary Key/Value Database is a type of NoSQL Database. NoSQL Database stands for Not Only SQL Database which means that the database can store heterogeneous data. The Key/Value database does not follow the conventional relational database way of storing the data. Every piece of data that needs to go into the DB, gets a key associated with it. Additionally, few other metadata also gets attached to the data. It stores data as hash table where each key is unique and the value can be string, array of strings, integer etc. Initially, data is stored in in-memory, but after particular time intervals or depending upon some specified condition, data is moved to disk in the form of Shards. Shards are nothing but XML…show more content…
1.2 Requirements and Responsibility Below are few of the requirements and responsibilities of the Key/Value database are listed below. • Shall implement a generic key/value in-memory database where each value consists of Metadata and Data. Metadata will consist of the following.  Name String  Text description of the item  Date-Time string recording the date and time the value was written to the database.  A finite number (possibly zero) of child relationships with other values. Each element of the child relationships collection is the key of another item in the database. Any item holding a key in this collection is the parent of the element accessed by the key. The data will consists of an instance object of the generic type. This might be a string, list, collection, custom collection. • Shall support addition and deletion of key/value pairs. • Shall support editing of values which includes the addition, deletion of relationships, editing metadata, and replacing an existing value 's instance with a new instance. • Editing keys is not allowed. Keys will be generated by the application and the keys shall be unique. • Shall, on command, write the database contents to an XML file. Shall make sure that the process be reversible, e.g., the database can be restored or augmented from an existing XML file as well as write its contents out to an XML file. • Shall accept a positive time interval or number of writes after which
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