What are the bind variable in oracle? What is the use of bind variables?

How to create the bind variable in oracle, types of bind variables.

A bind variable is a placeholder of a sql statement that must be replaced with the valid value or value address for the statement to execute successfully. Using the bind variables can write the sql statements that accepts inputs or parameters at run time.

Below example will explain in detail about bind variable:

Select * from emp where emp_id= :v_empid; In this statement v_empid is bind varaiable.

Referencing bind variables:

We can reference bind variable in pl/sql by typing : colon and immediate followed by the variable.

Ex: :retrive_val :=1;

To change this bind variable in sql*plus you must enter pl/sql block

Begin

  :retrive_val := 4;

End;

/

Displaying the bind variable

Sql> print retrive_val;