Found 1669 Articles for Big Data Analytics

The different user-friendly interfaces provided by the database management system (DBMS) are as follows −Menu-Based interfaces.Forms-based interfaces.Graphical user interfaces.Natural language interfaces.Speech input and output interfaces.Interfaces for parametric users.Interfaces for the database administrator (DBA).User friendly interfacesLet’s discuss the user-friendly interfaces provided by the DBMS in detail.Menu-based interfacesThese interfaces contain the lists of options through which the user is able to send the request.The Pull-down menus are a very popular technique in web-based user interfaces.These types of interfaces are mainly used by the web browsing users and web clients.Forms-based interfacesThese types of interfaces are displaying a form to each user. The user ... Read More

The database management system (DBMS) software is divided into several components. Each component will perform a specific operation. Some of the functions of the DBMS are supported by operating systems.The DBMS accepts the SQL commands that are generated from a variety of user interfaces, which produces a query evaluation plan, executes these plans against the database, and returns the answers.Let’s have a look on the major software components of DBMS with pictorial representation −ComponentsThe components of the DBMS are as follows −DBA − The Data Base Administrator (DBA) responsibility is to create the DBMS structure and have the ability to ... Read More

Entity relationship diagram is the graphical representation of entities and relationships among those entities in the database.ExampleConversion of ER diagrams to tablesFollow the steps given below for the conversion of the ER diagrams to tables in the database management system (DBMS) −Step 1 − Conversion of strong entitiesFor each strong entity create a separate table with the same name.Includes all attributes, if there is any composite attribute divided into simple attributes and has to be included.Ignore multivalued attributes at this stage.Select the p key for the table.Step 2 − Conversion of weak entityFor each weak entity create a separate table ... Read More

ER model stands for the Entity Relationship Model in the database management system (DBMS). It is the first step of designing to give the flow for a concept. It is the DFD (Data Flow Diagram) requirement of a company.It is the basic building block for relational models. Not that much training is required to design the database project. It is very easy to convert the E-R model into a relational table or to a normalized table.It is a high-level data model diagram that defines the conceptual view of the database. It acts as a blueprint to implement a database in ... Read More

Transaction Control language is a language that manages transactions within the database.It is used to execute the changes made by the DML statements.TCL CommandsTransaction Control Language (TCL) Commands are:Commit − It is used to save the transactions in the database.Rollback − It is used to restore the database to that state which was last committed.Begin − It is used at the beginning of a transaction.Savepoint − The changes done till savpoint will be unchanged and all the transactions after savepoint will be rolled back.ExampleGiven below is an example of the usage of the TCL commands in the database management system ... Read More

Data control language (DCL) is used to access the stored data. It is mainly used for revoke and to grant the user the required access to a database. In the database, this language does not have the feature of rollback.It is a part of the structured query language (SQL).It helps in controlling access to information stored in a database. It complements the data manipulation language (DML) and the data definition language (DDL).It is the simplest among three commands.It provides the administrators, to remove and set database permissions to desired users as needed.These commands are employed to grant, remove and deny ... Read More

The structured query language (SQL) commands deal with the manipulation of data present in the database that belongs to the DML or Data Manipulation Language. This includes most of the SQL statements.Examples of DMLThe examples of DML in the Database Management System (DBMS) are as follows −SELECT − Retrieve data from the database.INSERT − Insert data into a table.UPDATE − Update existing data within a table.DELETE − Delete records from a database table.Syntax for DML CommandsThe syntax for the DML commands are as follows −INSERTInsert command is used to insert data into a table.The syntax for INSERT command is as ... Read More

Data definition language (DDL) is a language that allows the user to define the data and their relationship to other types of data.Data Definition language statements work with the structure of the database table.Various data types used in defining columns in a database tableIntegrity and value constraintsViewing, modifying and removing a table structureDDL CommandsThe Data Definition Languages (DDL) Commands are as follows −Create − It is used to create a new table or a new database.Alter − It is used to alter or change the structure of the database table.Drop − It is used to delete a table, index, or ... Read More

Once data is stored or filled it requires manipulation like insertion, deletion, updating, and modification of data. For these operations a set of languages are provided by the database management system (DBMS). So, the database languages are used to read, update and store data in the database.The different types of DBMS languages are as follows −Data Definition Language (DDL) − Create, Drop, Truncate, Rename.Data Manipulation language (DML) − Select, Insert, Delete, Update.Data Control Language (DCL) − Revoke, Grant.Transaction Control Language (TCL) − Rollback, Commit.The DBMS languages are pictorially represented as follows −Data Definition Language (DDL)It is a language that allows ... Read More

A database administrator (DBA) is a person or group in charge of implementing DBMS in an organization. The DBA job requires a high degree of technical expertise. DBA consists of a team of people rather than just one person.The primary role of Database administrator is as follows −Database designPerformance issuesDatabase accessibilityCapacity issuesData replicationTable MaintenanceResponsibilities of DBAThe responsibilities of DBA are as follows −Makes the decision concerning the content of the database.Plans the storage structure and access strategy.Provides the support to the users.Defines the security and integrity checks.Interpreter backup and recovery strategies.Monitoring the performance and responding to the changes in the ... Read More