MB-8

Ushbu jadvalda qaysi ustun unikal qiymat qabul qiladi?

CREATE TABLE talaba (

id BIGSERIAL NOT NULL PRIMARY KEY,

first_name VARCHAR(50) NOT NULL,

last_name VARCHAR(50) NOT NULL,

email VARCHAR(50));

PRIMARY KEY – bu ...

• ma’lumotlarni yagonalik identifikatsiyasi

• ma'lumotlarni o'chiradi

• bir xil ma’lumotlarni kiritish imkonini beradi

• ma'lumotlarni nusxalaydi

Ma’lumotlarni yagonalik identifikatsiyasi - ...

PRIMARY KEY ni bir nechta ustunga qo'llash mumkin.

• Ha

• Yo'q

Jadvaldagi ustunlarga PRIMARY KEY ni o‘chirish so'rovi to'g'ri ko'rsatilgan javobni belgilang?

• ALTER TABLE table_name ADD PRIMARY KEY(field_name);

• ALTER TABLE table_name DROP CONSTRAINT field_name_pk;

• ALTER TABLE table_name DROP field_name;

• ALTER TABLE table_name ADD field_name <type>;

Jadvaldagi ustunlarga PRIMARY KEY ni qo'shish so'rovi to'g'ri ko'rsatilgan javobni belgilang?

• ALTER TABLE table_name ADD PRIMARY KEY(field_name);

• ALTER TABLE table_name DROP CONSTRAINT field_name_pk;

• ALTER TABLE table_name DROP field_name;

• ALTER TABLE table_name ADD field_name <type>;

Jadvaldagi yangi ustun qo'shish so'rovi to'g'ri ko'rsatilgan javobni belgilang?

• ALTER TABLE table_name ADD PRIMARY KEY(field_name);

• ALTER TABLE table_name DROP CONSTRAINT field_name_pk;

• ALTER TABLE table_name DROP field_name;

• ALTER TABLE table_name ADD field_name <type>;

Jadvaldagi ustunni o'chirish so'rovi to'g'ri ko'rsatilgan javobni belgilang?

• ALTER TABLE table_name ADD PRIMARY KEY(field_name);

• ALTER TABLE table_name DROP CONSTRAINT field_name_pk;

• ALTER TABLE table_name DROP field_name;

• ALTER TABLE table_name ADD field_name <type>;

DATABASE ro'yhatini ko'rish buyrug'i qanday?

• /l

• /c

• /d

• /dt

SQL tili kim tomonidan ishlab chiqarilgan?

• E. F. KODD

• B.PASKAL

• N.VIRT

• E.NOBEL