A foreign key is a column or set of columns in a table that refers to the primary key of another table. It is used to establish a relationship between two tables.When we study databases, one important idea is how ...Read more
What is a primary key?When we work with databases, one of the first ideas we must understand is how to uniquely identify each record. Just like every student in a class has a unique roll number, every row in a ...Read more
What is a table in SQL? In SQL, a table is the basic structure used to store data. The easiest way to understand it is to imagine a table as a carefully organised spreadsheet where information is ...Read more
What is SQL and what is it used for? When we talk about SQL, we are referring to Structured Query Language. It is the standard language used across the world for communicating with relational databases. ...Read more