Sql Select Distinct Clause
- The Select Distinct Clause is used to get different records.
- If we have dublicate records,only one of them is listed.
- The values of all listed columns must be exactly the same.
- For to bring records faster,at the subqueries are used often.
Sql Select Distinct Syntax
Select distinct columnNames from tableName
Sql Select Distinct Examples on Library Database
Example 1: List all students name,but the same names are listed ones.
Select distinct name from students
Example 2: List all students class names,but the same class names are listed ones.
Select distinct class from students
Example 3: List the books, that the student named John has read. The same records are listed ones.
Select distinct books.* from books join borrows on books.bookId = borrows.bookId join students on borrows.studentId = students.studentId