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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About MySQL

MySQL is a open-source, free and very popular relational database management system which is developed, distributed and supported by Oracle corporation.

Key Features:

  • Open-source relational database management systems.
  • Reliable, very fast and easy to use database server.
  • Works on client-server model.
  • Highly Secure and Scalable
  • High Performance
  • High productivity as it uses stored procedures, triggers, views to write a highly productive code.
  • Supports large databases efficiently.
  • Supports many operating systems like Linux*,CentOS*, Solaris*,Ubuntu*,Windows*, MacOS*,FreeBSD* and others.

Syntax help

Commands

1. CREATE

CREATE TABLE table_name (
                column1 datatype,
                column2 datatype,
                ....);

Example

CREATE TABLE EMPLOYEE (
  empId INTEGER PRIMARY KEY,
  name TEXT NOT NULL,
  dept TEXT NOT NULL
);

2. ALTER

ALTER TABLE Table_name ADD column_name datatype;

Example

INSERT INTO EMPLOYEE VALUES (0001, 'Dave', 'Sales');

3. TRUNCATE

TRUNCATE table table_name;

4. DROP

DROP TABLE table_name;

5. RENAME

RENAME TABLE table_name1 to new_table_name1; 

6. COMMENT

Single-Line Comments:

 --Line1;

Multi-Line comments:

   /* Line1,
   Line2 */

DML Commands

1. INSERT

INSERT INTO table_name (column1, column2, column3, ...) VALUES (value1, value2, value3, ...);

Note: Column names are optional.

Example

INSERT INTO EMPLOYEE VALUES (0001, 'Ava', 'Sales');

2. SELECT

SELECT column1, column2, ...
FROM table_name
[where condition]; 

Example

SELECT * FROM EMPLOYEE where dept ='sales';

3. UPDATE

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition; 

Example

UPDATE EMPLOYEE SET dept = 'Sales' WHERE empId='0001'; 

4. DELETE

DELETE FROM table_name where condition;

Example

DELETE from EMPLOYEE where empId='0001'; 

Indexes

1. CREATE INDEX

  CREATE INDEX index_name on table_name(column_name);
  • To Create Unique index:
  CREATE UNIQUE INDEX index_name on table_name(column_name);

2. DROP INDEX

DROP INDEX index_name ON table_name;

Views

1. Create a View

Creating a View:
CREATE VIEW View_name AS 
Query;

2. How to call view

SELECT * FROM View_name;

3. Altering a View

ALTER View View_name AS 
Query;

4. Deleting a View

DROP VIEW View_name;

Triggers

1. Create a Trigger

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 } */

2. Drop a Trigger

DROP TRIGGER [IF EXISTS] trigger_name;

Stored Procedures

1. Create a Stored Procedure

CREATE PROCEDURE sp_name(p1 datatype)
BEGIN
/*Stored procedure code*/
END;

2. How to call Stored procedure

CALL sp_name;

3. How to delete stored procedure

DROP PROCEDURE sp_name;

Joins

1. INNER JOIN

SELECT * FROM TABLE1 INNER JOIN TABLE2 where condition;

2. LEFT JOIN

SELECT * FROM TABLE1 LEFT JOIN TABLE2 ON condition;

3. RIGHT JOIN

SELECT * FROM TABLE1 RIGHT JOIN TABLE2 ON condition;

4. CROSS JOIN

SELECT select_list from TABLE1 CROSS JOIN TABLE2;