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Who is Database administrator? Write some functions of DBA in DBMS

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Database Administrator: One of the main reasons behind using DBMS is to have central control on both data and the applications access those data. The person who has such central control over the data is called a database administrator (DBA). Some of the functions of DBA are given below, Schema Definition: The DBA creates the … Read more

Describe different types of database users and their interfaces. DBMS

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There are about 4 different types of database users differentiated by their way of interaction with the database system. Brief description has been given below, Naive Users: This type of users generally interacts with the system through previously created programs. Such as, a user may use the system to transfer some balance from one account … Read more

What is transaction? What is Transaction Management? DBMS

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Transaction: A transaction is a collection of operations that performs a single logical function in a database application. Such as, when we want to add BDT 500 to account A and subtract BDT 500 from account B, that will be a transaction.  Transaction Management: Transaction is a unit of both atomicity and consistency. Thus it … Read more

Briefly describe the two-tier and three-tier architecture. DBMS

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Two-tier Architecture: In the two-tier architecture, the application is partitioned into a component that resides at the client machine and calls the database system functionality at the server machine using query language statements. Application program interface standards like ODBC and JDBC are used for interaction between the client and the server.  Three-tier Architecture: In three-tier … Read more

Describe the components of the query processor. DBMS

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Query Processor: As query is very much necessary to find out only the data user need from tons of data of the database, query processor is very important to process these query requests. Query processors come with the following components, DDL Interpreter: It interprets the DDL statements and records the definitions in data dictionary.  DML … Read more

Describe the data structures implemented by the storage manager.

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Data Structures Implemented by the Storage Manager: The storage manager implements several data structures as part of the physical system implementation. Data Files: It stores the database itself. Data Dictionary: It stores metadata about the structures of the database, in particular schema of the database. Indices: It can provide fast access to data items. It … Read more

What is storage manager? Describe the components of storage manager. DBMS

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What is storage manager? Describe the components of storage manager. DBMS

Storage Manager in a Database Management System in DBMS

The Storage Manager is a crucial component of a Database Management System (DBMS) that handles the storage, retrieval, and management of data on secondary storage devices. It acts as a bridge between the higher-level components of the DBMS, such as the query processor and transaction manager, and the physical storage media, typically disk drives.

At its core, the Storage Manager is responsible for efficiently organizing and managing the persistent storage of data. It provides an interface between the logical representation of data within the DBMS and the physical storage devices where the data resides. This involves translating high-level data operations and requests from the DBMS into low-level disk operations, ensuring that data is stored, retrieved, and managed reliably.

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In how many ways can database constraints be tested/evaluated? Describe briefly. DBMS

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Database Constraints: Database constraints are like conditions given to the manipulation of values of a field or attribute. Such as, we may limit the values under the payment attribute of a table that its value can never be less than BDT 350. Constraints can be tested as follows, Domain Constraints: Using domain constraints one can … Read more

Describe Data Definition Language (DDL). DBMS

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Data Definition Language (DDL): The specific language used to express the database schema by a set definitions is called Data Definition Language (DDL). The DDL is also used to specify additional properties of the data. Another special type of DDL, called the Data Storage and Definition Language, is used to specify storage and data access … Read more