SQL UNION ALL

SQL UNION ALL operatori

UNION ALL operatori ikki yoki undan ortiq SELECT iboralarining natijalar to‘plamini birlashtirish uchun ishlatiladi.

UNION ALL operatori har bir buyruqdagi barcha qatorlarni, jumladan har qanday takroriy qatorlarni ham o‘z ichiga oladi.

UNION ALL uchun talablar:

UNION ALL ichidagi har bir SELECT buyrug‘i bir xil sonli ustunlarga ega bo‘lishi kerak.
Ustunlar bir-biriga mos keluvchi ma’lumotlar turlariga ega bo‘lishi kerak
Har bir SELECT buyrug‘idagi ustunlar bir xil tartibda joylashishi kerak

SELECT column_name(s) FROM table1
UNION ALL
SELECT column_name(s) FROM table2;

Eslatma: Natijalar to‘plamidagi ustun nomlari odatda birinchi SELECT buyrug‘idagi ustun nomlariga teng bo‘ladi.

Quyida tanlanma "Customers" jadvali keltirilgan:

CustomerID	CustomerName	ContactName	Address	City	PostalCode	Country
1	Alfreds Futterkiste	Maria Anders	Obere Str. 57	Berlin	12209	Germany
2	Ana Trujillo Emparedados y helados	Ana Trujillo	Avda. de la Constitución 2222	México D.F.	05021	Mexico
3	Antonio Moreno Taquería	Antonio Moreno	Mataderos 2312	México D.F.	05023	Mexico

Va tanlanma "Suppliers" jadvali:

SupplierID	SupplierName	ContactName	Address	City	PostalCode	Country
1	Exotic Liquid	Charlotte Cooper	49 Gilbert St.	London	EC1 4SD	UK
2	New Orleans Cajun Delights	Shelley Burke	P.O. Box 78934	New Orleans	70117	USA
3	Grandma Kelly’s Homestead	Regina Murphy	707 Oxford Rd.	Ann Arbor	48104	USA

Quyidagi SQL "Customers" va "Suppliers" jadvallaridagi barcha mamlakatlarni (takroriy qiymatlar bilan birga) qaytaradi:

SELECT Country FROM Customers
UNION ALL
SELECT Country FROM Suppliers
ORDER BY Country;

Bu yerda "Customers" va "Suppliers" jadvallaridagi barcha Germaniya shaharlarini qaytarish uchun WHERE bandini qo‘shamiz:

SELECT City, Country FROM Customers
WHERE Country='Germany'
UNION ALL
SELECT City, Country FROM Suppliers
WHERE Country='Germany'
ORDER BY City;

Yutuqlaringizni kuzating – bu bepul!