In SQL (Structured Query Language), a DDL (Data Definition Language) command is used to define, manage, and manipulate the structure of database objects such as t… Read More

Understanding SQL constraints is crucial for database developers and administrators who want to build robust, error-free databases. SQL Constraints are statements used at the column or table… Read More

Some of the common MySQL constraints are: NOT NULL UNIQUE PRIMARY KEY FOREIGN KEY CHECK DEFAULT AUTO_INCREMENT Watch this video on MySQL Interview Questions and Answers NOT NULL NOT NULL… Read More

One to Many association links a parent entity with one or more child entities.   For example, an employee has one or more bank accounts.   There are two types of One to Many assoc… Read More

One to Many association links a parent entity with one or more child entities.   For example, an employee has one or more bank accounts.   There are two types of One to Many assoc… Read More

In this post, I am going to explain how to map an entity that contain embedded properties to a single database table using Embedded and Embeddable annotation.   For example, I have a co… Read More

Using @AttributeOverrides and @AttributeOverride anotations, we can override the column properties of embedded type. Example@Embedded@AttributeOverrides({@AttributeOverride( name = "firstNa… Read More

Introduction to Entity Framework in .Net Core Entity Framework in .Net Core is an Object Relational Mapper (ORM), and the tool makes mapping with objects in software simpler than the tables… Read More

Introduction to Comparison Operators in SQL Comparison operators in SQL are relational operators used to compare expressions’ values. These expressions can be a variable or column nam… Read More

Introduction to SQLAlchemy create_engine The create_engine is one of the modules in the SQLAlchemy project and it is more ever used in the callable object within the SQLAlchemy project incl… Read More

Definition of MySQL DROP TABLE MySQL DROP TABLE is a MySQL query statement that is responsible to drop a MySQL table existing in the database server. This is a MySQL command which is requir… Read More

Introduction to Teradata coalesce Teradata Coalesce is a Non-Null evaluation function. Basically, in all SQL environments, these Coalesce and Is Null functions help in the process of Non-Nu… Read More

In this post, I am going to explain how to model many to many mapping using a join table, where join table has a primary key column in it.   Requirement a.   One student can e… Read More

Hibernate is an ORM (Object-Relational Mapping) that is used to map the objects of Java classes with the relational database. It maps the java classes to database tables using XML configurat… Read More

Hibernate Associations technology handles how to persist java objects. But, it is possible only when the object has the XML-file that describes how to map it, or the object is annotated with… Read More