A clause in SQL is a built-in function that helps to fetch the required records from a database table. A clause receives a conditional expression, i.e. a column name or some terms involving the columns. The clause calculates the result based on the given statements in the expression.

A clause is a group of words that together form a phrase. There is a subject and a predicate in it. Another statement is that a sentence has to have a subject and a verb.

In the context of databases and SQL, a clause refers to a specific component or section of a SQL statement. Clauses are used to specify different aspects of the operation or query being performed. They help define conditions, criteria, sorting orders, and other parameters to customize the behavior of the SQL statement.