there is always at least one primary ke

Please help with the folllowing: Consider the following declaration of a relation schema     CREATE TABLE R   ( A int PRIMARY KEY,    B int not null,    C char (1) );  Then execution of which of the following queries will fail?  QI:  Insert INTO R (B, C) Values (353, 'B');  Q2: Insert INTO R (A, C) Values (111, ‘A’);  Q3: Insert INTO R (A, B) Values (222, 335);      Select one: a. Both QI and Q2  b. QI only  c. Both QI and Q3  d. Q2 only

Implement a new independent entity phone in the Sakila database. Attributes and relationships are shown in the following diagram: The diagram uses Sakila naming conventions. Follow the Sakila conventions for your table and column names: All lower case Underscore separator between root and suffix Foreign keys have the same name as referenced primary key Write CREATE TABLE and ALTER TABLE statements that: Implement the entity as a new phone table. Implement the has relationships as foreign keys in the Sakila customer, staff, and store tables. Remove the existing phone column from the Sakila address table. Step 2 requires adding a foreign key constraint to an existing table. Ex: ALTER TABLE customer ADD FOREIGN KEY (phone_id) REFERENCES phone(phone_id) ON DELETE SET NULL ON UPDATE CASCADE; Specify data types as follows: phone_id, phone_number, and country_code have data type INT. phone_type has date type VARCHAR(12) and contains strings like 'Home', 'Mobile', and 'Other'. Apply…

(Choose all of the correct superkeys.) Find all superkeys of the DEPARTMENT relation. Its primary key (PK) is underlined.                DEPARTMENT (number, dname, mgrssn, location)                PK = {dname, location} {number} {number, dname} {number, dname, mgrssn} {number, dname, mgrssn, location} {dname} {dname, mgrssn} {dname, mgrssn, location} {mgrssn} {mgrssn, location} {location} {number, dname, mgrssn} {number, dname, location} {number, mgrssn} {number, mgrssn, location} {number, location} {dname, location}