Which SQL clause is used to filter records?

The SQL clause used to filter records is the "WHERE" clause.

Here's a step-by-step explanation:

1. SQL, or Structured Query Language, is a language designed to manage data in relational databases.

2. In SQL, a query is a request for data from a database. This data is returned in a result table.

3. The "WHERE" clause is used in a SQL query to filter records and fetch only the necessary data.

4. It is used after the "FROM" clause in a SELECT statement and follows this basic format:

   SELECT column1, column2, ... FROM table_name WHERE condition;

5. The condition can be any condition of truth that returns the data you want. For example, if you want to select all records from a table named "Students" where the "Age" is greater than 20, your SQL query would look like this:

   SELECT * FROM Students WHERE Age > 20;

6. The "WHERE" clause can also be used with SQL commands other than SELECT, like UPDATE and DELETE, to specify exactly which records to update or delete.