DECLARE CURSOR TEMP IS SELECT TABLE_NAME,COLUMN_NAME,DATA_LENGTH FROM USER_TAB_COLUMNS WHERE DATA_TYPE = 'VARCHAR2'; STR VARCHAR2(100) := '';BEGIN FOR S IN TEMP LOOP STR := 'ALTER TABLE '||S.TABLE_NAME||' MODIFY('||S.COLUMN_NAME||' NVARCHAR2('||S.DATA_LENGTH||'))'; DBMS_OUTPUT.PUT_LINE(STR); EXECUTE IMMEDIATE STR ; END LOOP;END;
