oracle basics 2

--Tables and columns
select * from user_Tables;
select * from user_tab_columns;

rownumber / rownr: rownum;

select rownum as rownumber, ID from test;

simplest block:

set serveroutput on;
BEGIN
  DBMS_OUTPUT.put_line ('Hello World!');
END;

verwendung von variablen:

set serveroutput on;

DECLARE MyString VARCHAR2(100); --vorm block deklarieren

BEGIN

  MyString := 'Hello World 2';

  DBMS_OUTPUT.put_line (MyString);

END;

--variable aus select heraus befüllen

set serveroutput on;

DECLARE MyString VARCHAR2(100);

BEGIN

  select 'Hello World 3' into MyString from dual;

  DBMS_OUTPUT.put_line (MyString);

END;