Slide 9.14: Printing variables

Printing Variables

Sometimes we might want to print the value of a PL/SQL local variable.

A “quick-and-dirty” way is to store it as the sole tuple of some table and use a PL/SQL statement to print the table with a SELECT command.

Another way is to define a bind variable, which is the only kind that may be printed with a PRINT command. Bind variables are the kind that must be prefixed with a colon in PL/SQL statements, such as :new. The steps are as follows:

We declare a bind variable as follows:
```
     VARIABLE <name> <type>
```
where the type can be only one of three things: NUMBER, CHAR, or CHAR(n).

We may then assign to the variable in a following PL/SQL statement, but we must prefix it with a colon.

Finally, we can execute a statement
```
     PRINT :<name>;
```
outside the PL/SQL statement

Here is a trivial example, which prints the value 1.

 SQL> VARIABLE  x  NUMBER
 SQL> BEGIN  :x := 1;  END;
   2  /
 PL/SQL procedure successfully completed.

 SQL> PRINT :x;

          X
 ----------
          1