Question

我正在尝试创建一个如下所示的函数，但是会在标题中声明错误。

create or replace function gettaxmin(period_tax_type_id in double precision, tax_range in number) return double precision is
  Result double precision;
begin
  SELECT CASE WHEN max(tax_range) is null THEN 0 ELSE max(tax_range) END 

    FROM period_tax_rates WHERE (tax_range < 1) AND (period_tax_type_id = 2);
  return(Result);
end gettaxmin;

有什么想法吗？

Answer 1

您必须将SELECT语句的结果存储到变量中（在本例中为“Result”）：

create or replace function gettaxmin
            (period_tax_type_id in double precision, tax_range in number) 
    return double precision 
is
     Result double precision;
begin
  SELECT CASE WHEN max(tax_range) is null THEN 0 ELSE max(tax_range) END 
    INTO Result 
    FROM period_tax_rates WHERE (tax_range < 1) AND (period_tax_type_id = 2);
  return Result;
end gettaxmin;

Answer 2

您需要将结果存储在INTO结果

中

create or replace function gettaxmin(period_tax_type_id in double precision, tax_range in number) return double precision INTO
Result double precision;
begin
SELECT CASE WHEN max(tax_range) is null THEN 0 ELSE max(tax_range) END 

FROM period_tax_rates WHERE (tax_range < 1) AND (period_tax_type_id = 2);
return(Result);
end gettaxmin;

阅读http://dev.mysql.com/doc/refman/5.0/en/select-into.html

错误：PLS-00428：此select语句中需要一个into子句

2 个答案: