8-dars. SQL String funksiyalari (CONCAT, UPPER, LOWER, TRIM va boshqalar)

String funksiyalari matnli ma'lumotlar bilan ishlash uchun ishlatiladi.

Masalan:

Nomi	Vazifasi	Namuna	Natija
CONCAT	Bir nechta matnlarni birlashtiradi.	SELECT CONCAT (first_name,' - ', country) FROM customers	Maria - Germany John - USA Georg - UK
UPPER	Barcha harflarni katta harfga o'tkazadi.	SELECT UPPER (first_name) FROM customers	MARIA
LOWER	Barcha harflarni kichik harfga o'tkazadi.	SELECT LOWER (first_name) FROM customers	maria
TRIM	Matn boshidagi va oxiridagi bo'sh joylarni olib tashlaydi.	SELECT TRIM (first_name) FROM customers	Maria
REPLACE	Matn ichidagi bir qiymatni boshqasiga almashtiradi.	SELECT REPLACE (country, 'USA', 'United States') FROM customers	United States

Nomi	Vazifasi	Namuna	Natija
LEN	Matndagi belgilar sonini hisoblaydi.	SELECT first_name, LEN(first_name) AS Name_Length FROM customers	8

Nomi

Vazifasi

Namuna

Natija

LEN

Matndagi belgilar sonini hisoblaydi.

SELECT

first_name, LEN(first_name) AS Name_Length

FROM customers

Nomi	Vazifasi	Namuna	Natija
LEFT	Chap tomondan belgilangan miqdordagi belgini oladi.	SELECT first_name, LEFT (first_name, 2) FROM customers	Martin Ma
RIGHT	O'ng tomondan belgilangan miqdordagi belgini oladi.	SELECT first_name, RIGHT (first_name, 2) FROM customers	Martin in
SUBSTRING	Matnning istalgan qismidan ma'lumot oladi.	SUBSTRING (matn, boshlanish, uzunlik) SELECT first_name, SUBSTRING (first_name, 2, 3) FROM customers	Martin art

Email yaratish

SELECT
    CONCAT(LOWER(first_name),'@gmail.com')
FROM customers

Natija:

maria@gmail.com
john@gmail.com

Mamlakat kodini olish

SELECT
    country,
LEFT(country,2)
FROM customers

Ism uzunligini aniqlash

SELECT
    first_name,
    LEN(first_name)
FROM customers