The SQL Group by clause, as the name suggests, groups the similar column values, performs some aggregated function (like sum, count) and returns the consolidated result in groups.
The Where clause is used to filter the results that meet the given criteria. Where clause can be used with the Select statement to fetch only the required rows.
The Join clause is used to combine data of two or more tables into one temporary table. Joins in SQL combine data of two or more tables by the common keys.
The alter statement of SQL is used to change the existing table structure of the database. You can use the alter query for modifying existing column specifications. The specifications like data type, size etc.
A primary key is a field or column in a table that cannot contain the duplicate values or it uniquely identifies each row in a table.
The insert into statement is used to enter or insert data into the database tables. This chapter will explain how to use the insert statement with examples but first of all, let us look at its syntax.
The SQL stands for Structured Query Language, is a computer language designed to retrieve and manage data in the relational databases. The SQL is an ANSI standard which stands for American National Standards Institute.