Typically variables are declared in the DECLARE section, and are available inside BEGIN block. I find this style stiff and tedious.
Is it possible to declare variables inside the BEGIN block just when they are needed? It is stupid to declare new global variable, if it's needed just to store some temporary value for further calculations, queries and assertions.
Try this - I added comments in the code for you to understand the visibility domain of each variable. Also you can remove the comment from the last DBMS_OUTPUT to see that var2 is no longer available in the outer code.
set serveroutput on;
<<tag>>
DECLARE
var1 INT := 1; -- global variable
BEGIN
DECLARE
var1 INT := 2; -- local variable
var2 INT := 0;
BEGIN
DBMS_OUTPUT.PUT_LINE(var1); -- will display 2 (value of local var1);
DBMS_OUTPUT.PUT_LINE(tag.var1); -- will display 1 (value of global var1);
DBMS_OUTPUT.PUT_LINE(var2); -- will display 0 (value of local var2);
END;
DBMS_OUTPUT.PUT_LINE(var1); -- will display 1 (value of global var1);
-- DBMS_OUTPUT.PUT_LINE(var2); -- will crash since var2 is no longer in memory;
END;
All languages have own features. This is only instrument. May be you should divide your code into small chunks(procedures, functions)? If your code placed in 20-30 rows, you will not have problems with declaring variables. From smaller chuncks you can build bigger and reusable code.
Regards
