What is Transaction in DBMS ?
If we need one or more database access operations, we have a logical unit of processing called Database Transaction. In simple, database transactions represent real-world events of any enterprise. Database…
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DBMS
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Normal Forms in DBMS ?
There are 4 types of form in Normalization : First Normal Form(1NF) If a relation does not contain any multi valued attributes, then the relation is said to be in…
What are the types of databases ?
The different types of databases are: Hierarchical Database In this database data is organized in a tree like structure. Data is stored in the form of either top down or…
What is DBMS Queries ?
SQL Commands SQL commands are instruction which is used to communicate with the database. It is also used to perform specific tasks, functions, and queries of data It can also…
What is an XML Database in DBMS
For storing huge amount of data in xml format we use XML format. As XML is rapidly growing in every field, we need to have a secure place to store…
What is Relational Algebra in DBMS ?
A procedural query language which is used widely is known as Relational Algebra. Instances of relation are given as input data and we get output as occurrences of relations Relational…
What do you understand by Query Optimization ?
It is a phase which identifies a plan for evaluation query that has the least estimated cost. We can use query optimizer when there is lot of algorithms and methods…
Explain levels of abstraction in DBMS ?
There are 3 levels of abstraction in DBMS Physical Level It is the lowest level of data abstraction and is managed by DBMS. This level shows how the data is…
What is Hierarchical model in DBMS ?
Features of Hierarchical Model This model is based on the tree structure. This model contains a collection of records that are connected by each other by links. Tree structures that…
What is Join in DBMS and what are its types ?
DBMS join is a binary operation that allows combining join products and selecting in one single statement. If data needs to be retrieved from two or more tables, we can…
What is ER Model in DBMS ?
ER stands for Entity-Relationship model. It is a high level data model. If any data elements or relationship of any specified system can defined using this model. Conceptual design for…
What are the disadvantages of DBMS ?
High Cost Disadvantage of DBMS is its high cost of software and hardware. For users to use a DBMS they require a high speed processor and huge memory size and…
Different types of Keys in DBMS
There are 7 keys in DBMS Primary Key Key which is used to identify one and only instance of entity uniquely. An Enity can contains multiple keys, and keys which…
What are the data models in DBMS ?
There are 4 data models in DBMS Relational Data Model Edgar F.Codd described the model in 1969. Data are designed using rows and column within a table. So data and…
Difference between Trigger and Stored procedure in DBMS
Triggers Stored Procedures A Trigger is created in such a way that it fires when a specific event occurs. A group of sql commands that can be reused again and…
Difference between DBMS and File System
File System DBMS A software that manages and organizes the file in storage medium is called as file system. DBMS is software application that is used for creating, accessing and…
What are Database Management Tools ?
phpMyAdmin: PhpMyAdmin is the most popular open-source web-based database management tool by MySQL. Using phpMyAdmin we can create or manage databases, tables, DB users, optimize and check errors in your…
What is DBMS Utilities ?
Data Loading Utility: Data loading utility helps to load data from an external format without writing programs. Backup utility: In case of crashes and disasters this utility helps to take…
Difference between RDBMS and DBMS ?
DBMS RDBMS Data is stored in file format Data is stored in table format. Data is stored either in a hierarchical form or navigational form Tables have an identifier called…
Difference between Delete and Truncate
Delete Truncate Used to delete rows from a table based on the condition provided on the where clause. Used to delete the entire data from rows from the table.…
