oracle pl/sql笔记

oracle pl/sql笔记

I 、Instoduction

1、Instoduction to pl/sql

1)pl/sql block Structure

declare

begin

--statements

exception

end;

2)Block Types

Anonymous

declare

begin

--statements

exception

end;

Procedure

Procedure name is

begin

--statements

exception

end;

Function

Function name return datatype is

begin

--statements

return value;

exception

end;

SQL> set serveroutput on; SQL> declare   v_fname varchar2(20); begin   select first_name into v_fname from employees where employee_id=100;   dbms_output.put_line('the result is ' || v_fname); end;

2、Declaring PL/SQL Variables

1)Delimiters in String Literals

SQL> declare    2    v_event varchar2(15);   3  begin   4    v_event := q'! Father's day!';   5    dbms_output.put_line('3rd Sunday in June is: '|| v_event);   6    v_event := q'[Mother's day]';                   --或者两个‘   7    dbms_output.put_line('2nd Sunday in May is: ' || v_event);   8  end;   9  / 3rd Sunday in June is:  Father's day 2nd Sunday in May is: Mother's day PL/SQL procedure successfully completed. SQL>

2、Using a Qualifier with Nested Blocks

begin <<outer>> declare   v_father_name varchar2(20) :='Pitrick';   v_date_of_birth date := '10-apr-1985'; begin   declare     v_child_name varchar2(20) := 'nike';     v_date_of_birth date :='12-dec-2002';   begin     dbms_output.put_line('Father''s name: ' || v_father_name);     dbms_output.put_line('Date of Birth: ' || outer.v_date_of_birth);     dbms_output.put_line('Child''s Name: ' || v_child_name);     dbms_output.put_line('Date of Birth: ' || v_date_of_birth);   end; end; end outer; SQL> /   Father's name: Pitrick Date of Birth: 10-APR-85 Child's Name: nike Date of Birth: 12-DEC-02   PL/SQL procedure successfully completed   SQL> begin <<outer>> declare   v_father_name varchar2(20) :='Pitrick';   v_date_of_birth date := '10-apr-1985'; begin <<inner>>   declare     v_child_name varchar2(20) := 'nike';     v_date_of_birth date :='12-dec-2002';   begin     dbms_output.put_line('Father''s name: ' || v_father_name);     dbms_output.put_line('Date of Birth: ' || outer.v_date_of_birth);     dbms_output.put_line('Child''s Name: ' || v_child_name);     dbms_output.put_line('Date of Birth: ' || inner.v_date_of_birth);   end; end; end outer; SQL> /   Father's name: Pitrick Date of Birth: 10-APR-85 Child's Name: nike Date of Birth: 12-DEC-02   PL/SQL procedure successfully completed   SQL>