Tag: databases

Questions Related to databases

Which of the following constraint types can be used to ensure the value Of an INTEGER column references only positive values.
technology databases

  1. Unique

  2. Check

  3. Referential

  4. Informational

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Correct Option: B

Given that tables T1 and T2 contain the following rows : Table T1 : C1 C2 (5 4) (5 2) (5 5) Table T2 : C1 C2 (5 1) (5 2) (5 3) Which of the following queries will return only those rows that exists in T1 and not in T2 ?
technology databases

  1. Select * from T1 minus select * from T2

  2. Select * from T1 except select * from T2

  3. Select * from T1 union except select * from T2

  4. Select * from T1 not exists select * from T2

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Correct Option: B

Consider the following table called EMPLOYEES: ID FIRSTNAME LASTNAME JOB LEVEL 1 Paul Jones DBA 2 2 George Baker MGR 1 3 Roger Melvin CLERK 3 4 Jim Smith MGR 1 5 Kevin Street CLERK 3 6 Chris Eaton MGR 1 If the following SQL statement is executed, how many rows will be deleted? DELETE FROM employees WHERE 1 = 1
technology databases

  1. 0

  2. 1

  3. 3

  4. 6

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Correct Option: D

Given the following two tables: TAB1 C1 C2 1 Antarctica 2 Africa 3 Asia 4 Australia TAB2 CX CY 5 Europe 6 North America 7 South America Which of the following SQL statements will insert all rows found in table TAB2 into table TAB1?

technology databases

  1. INSERT INTO tab1 SELECT cx, cy FROM tab2

  2. INSERT INTO tab1 VALUES (tab2.cx, tab2.cy)

  3. INSERT INTO tab1 VALUES (SELECT cx, cy FROM tab2)

  4. INSERT INTO tab1 (c1, c2) VALUES (SELECT cx, cy FROM tab2)

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Correct Option: A

Given the following table and XML data stored in the CONTACTINFO column: CREATE TABLE clients( id INT PRIMARY KEY NOT NULL, name VARCHAR(50), status VARCHAR(10), contactinfo XML ) 25 EastCreek Toronto OntarioM8X-3T6 4165551358 9051112222 9051112222 by fax What is the result of the following XQuery expression? for $y in db2-fn:xmlcolumn('CLIENTS.CONTACTINFO')/Client//fax return $y

technology databases

  1. 4165551358

  2. 9051112222

  3. No results because there is no child element

  4. No results because the XQuery expression is not a valid FLWOR expression

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Correct Option: B

Given the following query: SELECT last_name, first_name, age, hire_date FROM employee WHERE age > 40 Which of the following clauses must be added to return the rows sorted by AGE, oldest first, and by LAST_NAME, from A to Z?
technology databases

  1. SORT BY age ASC, last_name

  2. SORT BY age DESC, last_name

  3. ORDER BY age DESC, last_name

  4. ORDER BY age ASC, last_name

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Correct Option: C

Given the table, Customer contain the following data Customer Table: Product-ID Quantity 1 5 2 3 3 4 The following sequence of statement performed at the single unit of work: UPDATE Customer SET Quantity = 3 WHERE Product-ID = 1; SAVEPOINT s1 ON ROLLBACK RETAIN CURSORS; UPDATE Customer SET Quantity = 5 WHERE Product-ID = 3; INSERT INTO Customer VALUES (5, 20); SAVEPOINT s2 ON ROLLBACK RETAIN CURSORS; INSERT INTO Customer VALUES (4, 10); ROLLBACK TO SAVEPOINT s1; INSERT INTO Customer VALUES (6, 10); INSERT INTO Customer VALUES (7, 15); COMMIT;
technology databases

  1. 1-5, 2-3, 3-5, 4-10, 5-20, 6-10, 7-15

  2. 1-3, 2-3, 3-4, 6-10, 7-15

  3. 1-3, 2-3, 3-4, 4-10, 5-20, 6-10, 7-15

  4. 1-3, 2-3, 3-4

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Correct Option: B

Given the following table and XML data stored in the EMPDETAILS column: CREATE TABLE employees (Emp-id INT PRIMARY KEY NOT NULL, Emp-name VARCHAR (20), Empdetails XML) The data in the EMPDETAILS are ProjectManager Chennai 987654 What is the result of the following XQuery Expression? For $y in db2-fn:xmlcolumn(EMPLOYEES. EMPDETAILS’)/Employee/designation return $y

technology databases

  1. ProjectManager

  2. ProjectManager

  3. chennai

  4. 987654

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Correct Option: A

In which situation is shredding XML data recommended?

technology databases

  1. When the data is naturally tabular

  2. When the number of nodes are volatile

  3. When the data by nature has sparse attributes

  4. When the data is of low volume and requires a complex star-schema topology

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Correct Option: A

Which of the following supports the XML data type?
technology databases

  1. A unique index

  2. .A composite index

  3. A check constraint

  4. .A generated column

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Correct Option: A