postgresql - GraphQL：添加计算字段时出错

Question

我正在尝试使用 hasura API 在模式“abc”中将计算字段添加到我的 graphql 表“用户”，但收到以下错误：

Saving computed field failed
in table "abc.user": in computed field "full_name": the computed field "full_name" 
cannot be added to table "abc.user" because the function "abc.fullname" is 
of type VOLATILE; cannot be added as a computed field

该功能已正确添加：

    CREATE OR REPLACE FUNCTION abc.fullname(userrow abc.user)
    RETURNS TEXT AS $$
BEGIN
    SELECT userrow.first_name || ' ' || userrow.last_name;
END;
$$ LANGUAGE plpgsql;

我可以从下拉列表中选择函数“全名”，但在添加计算字段时出现错误。任何指导表示赞赏。谢谢你。

Answer 1

错误信息试图告诉你。您需要显式声明该函数，immutable以便可以在计算列的定义中使用它：

create or replace function abc.fullname(userrow abc.user)
returns text immutable as $$
begin
    select userrow.first_name || ' ' || userrow.last_name;
end;
$$ language plpgsql;