开篇立意
oracle PLSQL函数中返回值有两种情况：
（1）使用return返回值；
（2）使用out修饰的参数（oracle不支持inout）
SQL> create function yu(id inout int) return int as
begin
null;
return 12;
end; 2 3 4 5
6 /
Warning: Function created with compilation errors.
SQL> show error function yu;
Errors for FUNCTION YU:
LINE/COL ERROR
-------- -----------------------------------------------------------------
1/22 PLS-00103: Encountered the symbol "INT" when expecting one of the
following:
:= . ) , @ % default character在一个函数中上述两种返回值的方法都可以使用在同一个函数中
create table nested_tab(id int, name varchar2(100), job varchar2(100), age int);
insert into nested_tab values (2, 'sdfsd', 'cvxvx', 14);
SQL> create or replace function nested_func(id1 out int, name1 out varchar2, job1 out varchar2, age1 out int)
return int as
id2 int;
name2 varchar2(100);
job2 varchar2(100);
age2 int;
begin
select * into id2, name2, job1, age1 from nested_tab where 2 3 4 5 6 7 8 age = 14;
id1 := id2;
name1 := name2;
job1 := job2;
age1 := age2;
begin
id1 := 45;
name1 := 'name';
job1 := 'job';
age1 := 45;
end;
return 0;
end;
/ 9 10 11 12 13 14 15 16 17 18 19 20 21
Function created.
SQL> create or replace function nested_func12(id1 out int, name1 out varchar2, job1 out varchar2, age1 out int)
return int as
retcode int;
begin
begin
retcode := nested_func(id1, name1, job1, age1);
end;
return 1;
end;
/ 2 3 4 5 6 7 8 9 10
Function created.
SQL> declare
id2 int;
name2 varchar2(100);
job2 varchar2(100);
age2 int;
retcode int;
begin
begin
retcode := nested_func12(id2, name2, job2, age2);
end;
dbms_output.put_line(id2 || name2 || job2 || age2);
end;
/ 2 3 4 5 6 7 8 9 10 11 12 13
45namejob45
PL/SQL procedure successfully completed.问题就出现了，LightDB是不支持这两者混用的，而且要有返回值。则这个参数必须既是输入又是输出，即inout，不然这个值是不能作为参数出现在函数中的。
问题解决
从plorasql内核代码可以知道，匿名块中函数的返回值是不能返回到上层的。涉及到执行器状态的切换，会释放函数内出现的变量的值，就算不释放也找不到函数内的变量和函数外的变量的对应值。因此解决这个问题需要分两步：
（1）解决执行器切换值释放问题；
（2）函数内的变量与函数外值的对应关系。
测试
CREATE TABLE fusettfundaccount (
branch_no numeric(10,0) NOT NULL DEFAULT 0,
fund_account character varying(18) NOT NULL DEFAULT ' '::character varying,
client_id character varying(18) NOT NULL DEFAULT ' '::character varying,
client_name character varying(60) NOT NULL DEFAULT ' '::character varying,
asset_prop character(1) NOT NULL DEFAULT ' '::bpchar,
fundacct_status character(1) NOT NULL DEFAULT ' '::bpchar,
remark character varying(2000) NOT NULL DEFAULT ' '::character varying,
position_str character varying(100) NOT NULL DEFAULT ' '::character varying,
client_group numeric(10,0) NOT NULL DEFAULT 0,
room_code numeric(10,0) NOT NULL DEFAULT 0,
organ_flag character(1) NOT NULL DEFAULT ' '::bpchar
) ;
CREATE UNIQUE INDEX idx_fusettfundacct ON fusettfundaccount USING btree (fund_account);
CREATE INDEX IF NOT EXISTS idx_fusettfundacct_id ON fusettfundaccount USING btree (client_id);
CREATE INDEX IF NOT EXISTS idx_fusettfundacct_pos ON fusettfundaccount USING btree (position_str);
insert into fusettfundaccount values (6666, '6661347', '6661347', 'F148', '9','0',' ', '06666000000000006661347', 666607, 666617,'0');
CREATE OR REPLACE FUNCTION ap_fusett_fundaccount_get(p_fund_account varchar2, INOUT p_branch_no numeric, INOUT p_client_id varchar2, INOUT p_client_name varchar2, INOUT p_asset_prop varchar2, INOUT p_remark varchar2, INOUT p_error_pathinfo varchar2, INOUT p_error_info varchar2, INOUT p_error_no numeric, INOUT p_error_id numeric, INOUT p_error_sysinfo varchar2)
RETURNS numeric
LANGUAGE plorasql
AS $function$
v_error_pathinfo_tmp varchar2(100);
begin
p_branch_no := 0;
p_client_id := ' ';
p_client_name := ' ';
p_asset_prop := ' ';
p_remark := ' ';
p_error_info := ' ';
p_error_no := 0;
p_error_id := 0;
p_error_sysinfo := ' ';
p_error_pathinfo := substr(p_error_pathinfo || '-->AP_FUSETT_FUNDACCOUNT_GET',1,500);
v_error_pathinfo_tmp := p_error_pathinfo;
begin
select/*AP_FUSETT_FUNDACCOUNT_GET*/ branch_no, client_id, client_name, asset_prop,
remark
into p_branch_no, p_client_id, p_client_name, p_asset_prop, p_remark
from fusettfundaccount
where fund_account = p_fund_account;
exception
when others then
p_error_no := 318100;
p_error_info := substrb(
'p_fund_account='||p_fund_account||']', 1, 500);
p_error_id := SQLCODE;
p_error_sysinfo := substr(SQLERRM,1,500);
return (p_error_no);
end;
return(0);
exception
when others then
p_error_no := 101;
p_error_info :='ִAP_FUSETT_FUNDACCOUNT_GET';
p_error_id := SQLCODE;
p_error_sysinfo := SQLERRM;
return(p_error_no);
end AP_FUSETT_FUNDACCOUNT_GET$function$;
DO $$
BEGIN
begin
$1 := AP_FUSETT_FUNDACCOUNT_GET ($2
,$3
,$4
,$5
,$6
,$7
,$8
,$9
,$10
,$11
,$12
);
end;
if ($1 = 0) then
$8 := $13;
end if;
END;
$$ (INT, CHAR, INT, char, char, char, char, char, char, INT, INT, varchar, char) using (0, 6661347, 0, null,null, 0, null, NULL, null, 0, 0, null,null) Language plorasql;
column1 | column2 | column3 | column4 | column5 | column6 | column7 | column8 | column9 | column10 | column11 | column12 | column13
---------+---------+---------+---------+---------+---------+---------+---------+---------+----------+----------+----------+----------
0 | 6661347 | 6666 | 6661347 | F148 | 9 | | | | 0 | 0 | |
(1 row)总结
在lightdb中，使用该功能需要注意：（1）函数用inout修饰需要返回的变量；（2）如果匿名块需要函数返回值时，使用inout修饰参数，return返回值必须要有具体的返回值，不然返回的就是一个record。