Время выполнения вложенных
подзапросов (вложенность 1, 2, …, 5)
Select * from
Abonents where Number in (select Number from Phones)
Select * from
Abonents where Number in (select Number from Phones where Type in (select
Type from Phone_type))
Select * from
Abonents where Number in (select Number from Phones where ATS_number in
(select ATS_number from ATS where Type in (select Type from ATS_type)))
Select * from
Abonents where Number in (select Number from Phones where ATS_number in
(select ATS_number from ATS where Type in (select Type from ATS_type
where Type in (select Type from Phone_type))))
Select * from
Abonents where Number in (select Number from Phones where Type in (select
Type from Phone_type where Type in (select Class from Phone_class where
Class in (select Type from ATS_type where Type in (select Region_code
from Regions)))))
Объединения
Объединение разного числа строк
(105, 2.5*105, 5*105, 7.5*105,
106) для разного числа столбцов (2, 3, 4, 5)
2 столбца
Select
Number, Priv_type from Phones where Number < 200000 UNION Select
Number, House from Abonents where Number < 200000
Select
Number, Priv_type from Phones where Number < 250000 UNION Select
Number, House from Abonents where Number < 250000
Select
Number, Priv_type from Phones where Number < 500000 UNION Select
Number, House from Abonents where Number < 500000
Select
Number, Priv_type from Phones where Number < 750000 UNION Select
Number, House from Abonents where Number < 750000
Select
Number, Priv_type from Phones UNION Select Number, House from Abonents
3 столбца
Select
Region_code, Surname, Name from Queue where ID <= 100000 UNION Select
Number, Surname, Name from Abonents where ID <=100000
Select
Region_code, Surname, Name from Queue where ID <= 250000 UNION Select
Number, Surname, Name from Abonents where ID <=250000
Select
Region_code, Surname, Name from Queue where ID <= 500000 UNION Select
Number, Surname, Name from Abonents where ID <=500000
Select
Region_code, Surname, Name from Queue where ID <= 750000 UNION Select
Number, Surname, Name from Abonents where ID <=750000
Select
Region_code, Surname, Name from Queue UNION Select Number, Surname, Name
from Abonents
4 столбца
Select
Region_code, Surname, Name, Patronymic from Queue where ID <= 100000
UNION Select Number, Surname, Name, Patronymic from Abonents where ID
<=100000
Select
Region_code, Surname, Name, Patronymic from Queue where ID <= 250000
UNION Select Number, Surname, Name, Patronymic from Abonents where ID
<=250000
Select
Region_code, Surname, Name, Patronymic from Queue where ID <= 500000
UNION Select Number, Surname, Name, Patronymic from Abonents where ID
<=500000
Select
Region_code, Surname, Name, Patronymic from Queue where ID <= 750000
UNION Select Number, Surname, Name, Patronymic from Abonents where ID
<=750000
Select
Region_code, Surname, Name, Patronymic from Queue UNION Select Number,
Surname, Name, Patronymic from Abonents
5 столбцов
Select
Priv_exist, Region_code, Surname, Name, Patronymic from Queue where ID
<= 100000 UNION Select Number, House, Surname, Name, Patronymic from
Abonents where ID <=100000
Select
Priv_exist, Region_code, Surname, Name, Patronymic from Queue where ID
<= 250000 UNION Select Number, House, Surname, Name, Patronymic from
Abonents where ID <=250000
Select
Priv_exist, Region_code, Surname, Name, Patronymic from Queue where ID
<= 500000 UNION Select Number, House, Surname, Name, Patronymic from
Abonents where ID <=500000
Select
Priv_exist, Region_code, Surname, Name, Patronymic from Queue where ID
<= 750000 UNION Select Number, House, Surname, Name, Patronymic from
Abonents where ID <=750000
Select
Priv_exist, Region_code, Surname, Name, Patronymic from Queue UNION
Select Number, House, Surname, Name, Patronymic from Abonents
