DELETE Clause in SQL

The DELETE clause is used to remove or delete one or more tuples (rows) from a database table. It allows us to selectively remove data from a table based on specific conditions or remove all the data from the table.

Syntax:
The basic syntax of the DELETE clause is as follows:
```
DELETE FROM table_name
WHERE condition;
```
- DELETE FROM: The DELETE statement starts with the DELETE FROM clause followed by the table name from which the tuples are to be deleted.
- WHERE: The WHERE clause is optional but is used to specify the condition that must be met for the deletion to take place. If no WHERE clause is specified, all the tuples in the table will be deleted.

Example:
Let's consider a table named "Students" with the following structure and data:
```
+----+----------+-------+
| ID | Name | Grade |
+----+----------+-------+
| 1 | John | A |
| 2 | Alice | B |
| 3 | Bob | C |
| 4 | Charlie | A |
+----+----------+-------+
```
To delete a single tuple with ID=3, we can use the following DELETE statement:
```
DELETE FROM Students
WHERE ID = 3;
```
After executing the above statement, the table will look like this:
```
+----+----------+-------+
| ID | Name | Grade |
+----+----------+-------+
| 1 | John | A |
| 2 | Alice | B |
| 4 | Charlie | A |
+----+----------+-------+
```
Similarly, if we want to delete all tuples with Grade='A', we can use the following DELETE statement:
```
DELETE FROM Students
WHERE Grade = 'A';
```
After executing the above statement, the table will be:
```
+----+----------+-------+
| ID | Name | Grade |
+----+----------+-------+
| 2 | Alice | B |
+----+----------+-------+
```

In conclusion, the DELETE clause in SQL is used to delete one or more tuples from a database table based on specified conditions. It allows for selective removal of data and helps in managing the data in the database effectively.