SELECT fname, lname /* select query */
FROM myDb.students
WHERE student_id = 1;
UPDATE myDB.students /* action query */
SET fname = 'Free Time', lname = 'Learning'
WHERE student_id = 1;SELECT name, email, mob, address
FROM myDb.contacts
WHERE roll_no IN (
SELECT roll_no
FROM myDb.students
WHERE subject = 'Maths');SELECT * FROM myDB.students;CREATE VIEW view_name AS
SELECT column_name(s)
FROM table_name
WHERE conditionCREATE OR REPLACE VIEW view_name AS
SELECT column_name(s)
FROM table_name
WHERE conditionSELECT column_name(s) FROM table_name WHERE condition;SQL> SAVEPOINT A
SQL> INSERT INTO TEST VALUES (1,'Savepoint A');
1 row inserted.
SQL> SAVEPOINT B
SQL> INSERT INTO TEST VALUES (2,'Savepoint B');
1 row inserted.
SQL> ROLLBACK TO B;
Rollback complete.
SQL> SELECT * FROM TEST;
ID MSG
-------- -----------
1 Savepoint Avariable_name table_name%rowtype;SQL> create table test (sno number(10), primary key, name varchar2(10));SELECT A.emp_name AS "Employee" /* Alias using AS keyword */
B.emp_name AS "Supervisor"
FROM employee A, employee B /* Alias without AS keyword */
WHERE A.emp_sup = B.emp_id;DELETE FROM Candidates
WHERE CandidateId > 1000;TRUNCATE TABLE Candidates;DROP TABLE Candidates;SELECT * FROM Worker ORDER BY Salary DESC LIMIT 10;​SELECT TOP 10 * FROM Worker ORDER BY Salary DESC;​SELECT * FROM (SELECT * FROM Worker ORDER BY Salary DESC)
WHERE ROWNUM <= 10;SELECT Salary FROM Worker ORDER BY Salary DESC LIMIT n-1,1;SELECT TOP 1 Salary
FROM (
SELECT DISTINCT TOP n Salary
FROM Worker
ORDER BY Salary DESC
)
ORDER BY Salary ASC;Select distinct W.WORKER_ID, W.FIRST_NAME, W.Salary
from Worker W, Worker W1
where W.Salary = W1.Salary
and W.WORKER_ID != W1.WORKER_ID;(SELECT * FROM Worker)
INTERSECT
(SELECT * FROM WorkerClone);SELECT * FROM WORKER
WHERE WORKER_ID <= (SELECT count(WORKER_ID)/2 from Worker);Select * from Worker where
WORKER_ID = (SELECT max(WORKER_ID) from Worker);SELECT DEPARTMENT, sum(Salary) from worker group by DEPARTMENT;