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DECLARE
a NUMBER;
b NUMBER;
BEGIN
a := 1;
b := 1;
DBMS_OUTPUT.PUT_LINE('sum = '|| a+b);
END;
/
ORA-06502: PL/SQL: numeric or value error: character to number conversion error
ORA-06512: at line 7
DECLARE
a NUMBER;
b NUMBER;
BEGIN
a := 1;
b := 1;
DBMS_OUTPUT.PUT_LINE('sum = '|| (a+b));
END;
/
1 rows affected
dbms_output:
sum = 2