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Statement 1: We can create foreign key constraints on relational schema derived from ER diagram Statement 2: Relational schema cannot be derived from an ER diagram

Statement 1: We can create foreign key constraints on relational schema derived from ER diagram Statement 2: Relational schema cannot be derived from an ER diagram Correct Answer Statement 1 is true and Statement 2 is false

We can create foreign key constraints on relational schema derived from ER diagram and also it is possible to derive relational schema from ER diagrams.

Related Questions

Consider the following four relational schemas. For each schema, all non-trivial functional dependencies are listed. The underlined attributes are the respective primary keys. Schema I: Field ‘courses’ is a set-valued attribute containing the set of courses a student has registered for. Non-trivial functional dependency: rollno → courses Schema II: Non-trivial functional dependencies: rollno, courseid → email email → rollno Schema III: Non-trivial functional dependencies: rollno, courseid → marks, grade marks → grade Schema IV: Non-trivial functional dependencies: rollno, courseid → credit courseid → credit Which one of the relational schemas above is in 3NF but not in BCNF?
Given the following statements: S1: A foreign key declaration can always be replaced by an equivalent check assertion in SQL. S2: Given the table R (a, b, c) where a and b together form the primary key, the following is a valid table definition. CREATE TABLE S (                 a INTEGER,                 d INTEGER,                 e INTEGER,                 PRIMARY KEY (d)                 FOREIGN KEY (a) references R) Which one of the following statements is CORRECT?
Consider the relational schema given below, where eId of the relation dependent is a foreign key referring to empId of the relation employee. Assume that every employee has at least one associated dependent in the dependent relation. Employee (empId, empName, empAge) Dependent(depId, eId, depName, depAge) Consider the following relational algebra query: ΠempId(employee)-ΠempId (employee⋈(empId = eID)∧(empAge ≤ depAge)dependent) The above query evaluates to the set of empIds of employees whose age is greater than that of
Consider the following statements S1 and S2 about the relational data model: S1: A relation scheme can have at most one foreign key. S2: A foreign key in a relation scheme R cannot be used to refer to tuples of R. Which one of the following choices is correct? 
Public key encryption uses multiple keys.ne key is used to encrypt data, while another is used to decrypt data.he key used to encrypt data is called the _______ key, while the key used to decrypt data is called the ________ key.
The following sentences have been given in a jumbled manner. Un-jumble the sentences and answer the option which describes the order of sentences in a correct manner.  A. India's government is in talks with foreign lenders to provide as much as $14.5 billion in credit to millions of its small firms, two officials said, in a sign, the country's banking system may not be robust enough to do the job on its own B. India's micro, small and medium enterprise(MSME) ministry is discussing the proposal to pull in foreign banks with the country's ministry of finance, which will make a final call. C. The push for foreign loans comes on the heels of the Indian government's announcement earlier this month that it plans to borrow about 700 billion rupees by issuing overseas sovereign bonds. D. The government is in discussions with multiple foreign lenders, including Germany's state-owned development bank KfW Group, the World Bank and some Canadian institutions to extend lines of credit to small enterprises E. One official said that the government plans to source up to 1 trillion Indian rupees of loans from foreign institutions because Indian banks were not in a position to provide enough capital for the small business sector, which is seen as critical to job creation.
Which of the following statement is/are correct?
1. The Government of India has power to cede Indian territory in favour of a foreign country.
2. Any territory of India can be ceded in favour of the foreign country only if there is an agreement between the heads of the two States.
3. Indian territory can be ceded to a foreign country only in accordance with Article 368 of the Constitution of India.
4. The Indian territory can not be ceded to any foreign country.
Select the correct answer:
Consider the following relational schema: employee(empId,empName,empDept) customer(custId,custName,salesRepId,rating) salesRepId is a foreign key referring to empId of the employee relation. Assume that each employee makes a sale to at least one customer. What does the following query return? SELECT empName FROM employee E WHERE NOT EXISTS (SELECT custId FROM customer C WHERE C.salesRepId = E.empId AND C.rating <> ’GOOD’);
What is the result of compiling and running the following code? class Base{ public Base(){ System.out.print("Base"); } } public class Derived extends Base{ public Derived(){ this("Examveda"); System.out.print("Derived"); } public Derived(String s){ System.out.print(s); } public static void main(String[] args){ new Derived(); } }
Let relation R2 has a Foreign Key that refers to Primary Key of relation R1. Which of the following operations may cause violation of referential integrity constraints? I: insert into R1 II: insert into R2 III: delete from R1 IV: delete from R2