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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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…
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….