ЗАДАНИЕ 1.1. Приемы моделирования Классификаторов / main_procedures

/*Добавление новой ЕИ в таблицу*/
create or replace function ins_ei(CODE integer, SHORT_NAME varchar(10), NAME varchar(50))
    returns INTEGER
as
'
    insert into EI(SHORT_NAME, NAME, CODE)
    values (CODE, SHORT_NAME, NAME);
    select 1
'
    LANGUAGE sql;

/*Операция добавления нового класса в классификатор изделий*/
CREATE OR REPLACE FUNCTION ins_class(main_class INTEGER, short_name VARCHAR(10), name VARCHAR(50), base_ei INTEGER)
    returns INTEGER
as
'
    begin
        if (exists(
                select BASE_EI
                from EI
                where EI.EI_ID = base_ei)
            ) then
            insert into PRODUCT_CLASS(MAIN_CLASS, SHORT_NAME, NAME, BASE_EI)
            values (main_class, short_name, name, base_ei);
            return 1;
        end if;

        insert into PRODUCT_CLASS(MAIN_CLASS, SHORT_NAME, NAME, BASE_EI)
        values (NULL, short_name, name, NULL);
        return 1;
    end;
'
    LANGUAGE plpgsql;


/*Поиск всех подклассов класса*/
CREATE OR REPLACE FUNCTION find_gr_gr(class INTEGER)
    returns TABLE(ID  integer, MAIN INTEGER, NAME VARCHAR(50), BASE INTEGER)
as
$$
    begin
        return QUERY
        SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS,PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
        FROM PRODUCT_CLASS
        WHERE ID_CLASS = class
        union
        (WITH RECURSIVE r AS (
            SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS,PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
            FROM PRODUCT_CLASS
            WHERE MAIN_CLASS = class

            UNION

            SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS, PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
            FROM PRODUCT_CLASS
                JOIN r
                    ON PRODUCT_CLASS.MAIN_CLASS = r.ID_CLASS
        )
        SELECT * from r)
        order by id_class;
    end;
$$
    LANGUAGE plpgsql;

/*Поиск всех родителей класса*/
CREATE OR REPLACE FUNCTION find_parent(class INTEGER)
    returns TABLE(ID  integer, MAIN INTEGER, NAME VARCHAR(50), BASE INTEGER)
as
$$
    begin
        return QUERY
        SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS, PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
        FROM PRODUCT_CLASS
        WHERE ID_CLASS = class
        union
        (WITH RECURSIVE r AS (
            with t as (SELECT MAIN_CLASS AS parent FROM PRODUCT_CLASS
            WHERE ID_CLASS = class)

            SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS,PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
            FROM PRODUCT_CLASS, t
            WHERE ID_CLASS = t.parent

            UNION

            SELECT PRODUCT_CLASS.ID_CLASS, PRODUCT_CLASS.MAIN_CLASS, PRODUCT_CLASS.NAME, PRODUCT_CLASS.BASE_EI
            FROM PRODUCT_CLASS
                JOIN r
                    ON PRODUCT_CLASS.ID_CLASS = r.MAIN_CLASS
        )
        SELECT * from r)
    order by id_class DESC;
    end;
$$
    LANGUAGE plpgsql;

/*Добавление продукции в таблицу*/
create or replace function ins_prod(ID_CL integer, SHORT_NAME varchar(10), NAME varchar(50))
    returns INTEGER
as
'
begin
    if (exists(
                select ID_CLASS
                from PRODUCT_CLASS
                where PRODUCT_CLASS.ID_CLASS = ID_CL)
            ) then
            insert into PROD(ID_CL, short_name, NAME)
            values (ID_CL, SHORT_NAME, NAME);
            return 1;
        end if;
    insert into PROD(ID_CL, short_name, NAME)
    values (NULL, SHORT_NAME, NAME);
    return 1;
end;
'
    LANGUAGE plpgsql;

/*Вывести список всех продукции указанного класса*/
create or replace function FIND_LIST(class integer)
returns TABLE(ID integer, prod_name VARCHAR(50), shotr_NAME VARCHAR(10), ei_name varchar(10), class_id INTEGER, class_name varchar(50))
as
$$
    begin
        return QUERY
        with t as (select * from find_gr_gr(class))
        select ID_PROD, PROD.NAME, PROD.SHORT_NAME, ei.name, prod.id_cl, PRODUCT_CLASS.name from prod
        inner join PRODUCT_CLASS on PRODUCT_CLASS.id_class = prod.id_cl
        inner join EI on EI.ei_id = PRODUCT_CLASS.base_ei
        where prod.id_cl = any(select t.id from t);
    end;
$$
    LANGUAGE plpgsql;