A temporary work area known as a cursor is established in the system memory whenever DML statements are performed. Although a cursor may contain many rows, processing−wise, only one row is taken into consideration. Cursors are very helpful to the kind of DBMSs like Oracle, Mysql, SQL servers, etc. A cursor is a control structure to go through database records and is used in databases. Cursors are of two types Implicit Cursors Explicit Cursors Implicit Cursors If you don't use an explicit cursor for the statement, Oracle will create implicit cursors while the SQL statement is performed. Some ... Read More

Catalogs are referred to as database systems that contain information about objects present in the database itself or the database itself that contains metadata of a distributed database. Catalog management is to be handled effectively as it will affect the performance of site autonomy, view management, and data distribution and replication. Distributed catalog management knows the data distribution across the sites. If any fragmentation and replication of relation occur, then with the help of a distributed catalog, we can uniquely find the replica of each fragment. Global relation name is shown as , and Global replica name is ... Read More

Distributed Consensus Distributed consensus plays a vital role in decentralized systems, ensuring reliability, fault tolerance, and agreement among multiple parties. Distributed consensus occurs when multiple parties try to accept some values, which is difficult as agreeing is not easy. The complexity to achieve consensus increases as an increase in the number of parties agree on an agreement. Various sites are working together to do a common task by communicating with each other via a network and agreeing to some values which come under distributed consensus. Importance of Distributed Consensus in Distributed Systems In a distributed or decentralized multi−agent platform, ... Read More

The transfer of data for storage at various computers or locations connected over a network is known as a distributed database. It may alternatively be described as a database that gathers information from several databases using independent computers linked by data communication connections. Compared to centralized database systems, distributed databases can offer higher availability and dependability. This is so that the system can continue to function even if one or more sites go down. A distributed database system can perform more effectively by distributing the burden and using the information across several sites. Design Considerations ... Read More

A document is a record in a document−based database that contains data on an item and any associated metadata. Field−value pairs form documents that can include a variety of data types like characters, integers, dates, arrays, and objects. They are commonly saved in XML, JSON, or BSON formats. Data retrieval and processing are made simple by the unique identifiers assigned to each document in the database. Documents do not have a set schema, therefore they do not all need to contain the same fields in a collection. This adaptability makes it possible to store several data structures in ... Read More

Database management systems (DBMS) employ the non−procedural query language known as Domain Relational Calculus (DRC). DRC focuses simply on what data to collect without outlining the techniques for retrieval, as opposed to Relational Algebra, which provides methods and procedures for fetching data. It offers a declarative method of database querying. Syntax { | P(x1, x2, ..., xn) } Here, refers to the resulting domain variable P(x1, x2, ..., xn) refers to the condition equivalent to the predicate calculus. Example 1 This example shows us to solve the query which is how to find the names ... Read More

Double buffering is essential for improving user experience and performance. This method is extensively used to reduce delays, increase performance, and enable smooth multitasking in database management systems, streaming media applications, and graphics rendering. In order to optimise data transit and processing, double buffering is used which is a programming approach that uses two buffers or temporary storage spaces. It enables the execution of input and output processes simultaneously, thereby minimising delays and enhancing system performance as a whole. Double buffering allows for efficient multitasking and effective resource management by using one buffer for data storage while the other ... Read More

A schema is a logical structure that stores database objects in SQL Server. It offers a method for classifying and organizing database items including tables, views, and processes. There could be instances where you need to delete a schema from your database. The SQL Server DROP SCHEMA command is useful in this situation. We can delete a schema from the database using the DROP SCHEMA statement. For database administrators and developers who wish to effectively control the structure of their databases, the Drop statement is a crucial tool. Syntax DROP SCHEMA [ IF EXISTS ] schema_name; Here, If ... Read More

Making the best option for the organisation's Database Management System (DBMS) is crucial since it may have a big influence on the business's operations and financial resources. When choosing a DBMS, a number of variables come into play, including technical concerns, organisational politics, and economic issues. We may make an educated choice that is in line with the financial objectives and needs of the organisation by being aware of these economic considerations. Factors to Consider Software Acquisition Cost The cost of a software purchase is one of the main economic aspects to consider when selecting a DBMS. This refers ... Read More

Embedded SQL is a powerful method that allows the integration of high−level programming languages with database management systems (DBMS). It acts as a bridge between applications and databases which helps in data manipulation and communication. Various database management systems offer embedded SQL, giving developers the freedom to select the one that best serves their requirements. Popular DBMS that support Embedded SQL are Altibase, IBM Db2, Microsoft SQL Server, Mimer SQL, Oracle Database, PostgreSQL, and SAP Sybase. Need of Embedded SQL The goal to make database interactions simpler for application developers and end users determines the demand for embedded SQL. ... Read More