SQL
PL/SQL Tutorial
PL/SQL tutorial provides basic and advanced concepts of SQL. Our PL/SQL tutorial is designed for beginners and professionals. PL/SQL is a block structured language that…
SQL vs NoSQL
There are a lot of databases used today in the industry. Some are SQL databases, some are NoSQL databases. The conventional database is SQL database…
Alternate Key
Alternate key is a secondary key it can be simple to understand by an example: Let’s take an example of student it can contain NAME,…
Unique Key
A unique key is a set of one or more than one fields/columns of a table that uniquely identify a record in a database table….
Composite Key
A composite key is a combination of two or more columns in a table that can be used to uniquely identify each row in the…
FOREIGN KEY
In the relational databases, a foreign key is a field or a column that is used to establish a link between two tables. In simple…
PRIMARY KEY
A column or columns is called primary key (PK) that uniquely identifies each row in the table. If you want to create a primary key,…
SQL CROSS JOIN
When each row of first table is combined with each row from the second table, known as Cartesian join or cross join. In general words…
SQL FULL JOIN
The SQL full join is the result of combination of both left and right outer join and the join tables have all the records from…
SQL RIGHT JOIN
The SQL right join returns all the values from the rows of right table. It also includes the matched values from left table but if…
