oracle 函数生成流水号

code_base 表

create table CODE_BASE

(

code VARCHAR2(20),

vdate VARCHAR2(20),

seq NUMBER

)

CREATE OR REPLACE FUNCTION create_code

(p_code varchar2,p_length number) return VARCHAR2 as PRAGMA AUTONOMOUS_TRANSACTION;

v_count number;

v_code varchar2(40);

v_lock code_base%rowtype;

begin

select count(1)

into v_count

from code_base c

where c.code = p_code

and c.vdate = to_char(sysdate, 'yymmdd');

dbms_output.put_line(v_count) ;

if v_count < 1 then

insert into code_base(code,vdate,seq)

values(p_code,to_char(sysdate, 'yymmdd'),1);

end if;

select * into v_lock from code_base c where c.code = p_code

and c.vdate = to_char(sysdate, 'yymmdd') for update;

select c.code||c.vdate||lpad(c.seq, p_length, 0) into v_code from code_base c where c.code = p_code

and c.vdate = to_char(sysdate, 'yymmdd');

update code_base c

set c.seq=c.seq+1

where c.code = p_code and c.vdate = to_char(sysdate, 'yymmdd');

commit;

return v_code;

end;