1) Find the titles of courses in the Comp. Sci. department that have 3 credits. MariaDB [university1]> select course_name from course where dept_name='Comp_Sci' and credits=3; 2) Find the highest salary of any instructor. mysql> select max(salary) from instructor; 3) Find the department names of all instructors. mysql> Select dept_name from instructor; 4) Find the department names of all instructors(eliminate duplicate entry). mysql> Select distinct dept_name from instructor; 5) Find the names of all instructors in the computer science department who have salary greater than 70000. mysql> Select name from instructor where dept_name='computerscience' and salary>70000; 6) Retrieve the names of all instructor along with their department names,department building. MariaDB [university1]> select inst_name, department.dept_name, building from department, instructor where department.dept_name=instructor.dept_name; 7) Find the names and course_id of all instructors. mysql> Select name,course_id from instructor,teaches where instructor.id=teaches.id; 8) Find the names and course_id of all instructors using tuple variable. mysql> Select name as n,course_id as c from instructor, teaches where instructor.id=teaches.id; 9) For all instructor in the university who have taught some course,find their names and the course id of all course they taught. mysql> Select I.name,T.course_id from instructor as I,teaches as T where I.id=T.id; 10) Find the names of all instructor whose salary is grater than at least one instructor in the biology department. Select name from instructor where salary>some( select salary from instructor where dept_name= ‘biology’); 11)Find the names of all departments whose building name includes substring ‘watson’ mysql> Select dept_name from department where buliding like '%watson%'; 12)Find the names of all departments whose building name beginning with ‘wat’. mysql> Select dept_name from department where buliding like 'wat%'; 13)Find the names of all departments whose building name ending with ‘son’. mysql> Select dept_name from department where buliding like '%son'; 14)Find the names of all departments whose building name consist of 6 letters. mysql> Select dept_name from department where buliding like '______'; 15)To list in alphabetic order all instructors in the physics department. select inst_name from instructor where dept_name='Comp_Sci' ;
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MySQL is a open-source, free and very popular relational database management system which is developed, distributed and supported by Oracle corporation.
CREATE TABLE table_name (
column1 datatype,
column2 datatype,
....);
CREATE TABLE EMPLOYEE (
empId INTEGER PRIMARY KEY,
name TEXT NOT NULL,
dept TEXT NOT NULL
);
ALTER TABLE Table_name ADD column_name datatype;
INSERT INTO EMPLOYEE VALUES (0001, 'Dave', 'Sales');
TRUNCATE table table_name;
DROP TABLE table_name;
RENAME TABLE table_name1 to new_table_name1;
--Line1;
/* Line1,
Line2 */
INSERT INTO table_name (column1, column2, column3, ...) VALUES (value1, value2, value3, ...);
Note: Column names are optional.
INSERT INTO EMPLOYEE VALUES (0001, 'Ava', 'Sales');
SELECT column1, column2, ...
FROM table_name
[where condition];
SELECT * FROM EMPLOYEE where dept ='sales';
UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;
UPDATE EMPLOYEE SET dept = 'Sales' WHERE empId='0001';
DELETE FROM table_name where condition;
DELETE from EMPLOYEE where empId='0001';
CREATE INDEX index_name on table_name(column_name);
CREATE UNIQUE INDEX index_name on table_name(column_name);
DROP INDEX index_name ON table_name;
Creating a View:
CREATE VIEW View_name AS
Query;
SELECT * FROM View_name;
ALTER View View_name AS
Query;
DROP VIEW View_name;
CREATE TRIGGER trigger_name trigger_time trigger_event
ON tbl_name FOR EACH ROW [trigger_order] trigger_body
/* where
trigger_time: { BEFORE | AFTER }
trigger_event: { INSERT | UPDATE | DELETE }
trigger_order: { FOLLOWS | PRECEDES } */
DROP TRIGGER [IF EXISTS] trigger_name;
CREATE PROCEDURE sp_name(p1 datatype)
BEGIN
/*Stored procedure code*/
END;
CALL sp_name;
DROP PROCEDURE sp_name;
SELECT * FROM TABLE1 INNER JOIN TABLE2 where condition;
SELECT * FROM TABLE1 LEFT JOIN TABLE2 ON condition;
SELECT * FROM TABLE1 RIGHT JOIN TABLE2 ON condition;
SELECT select_list from TABLE1 CROSS JOIN TABLE2;