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

-- -- insert
-- INSERT INTO EMPLOYEE VALUES (0001, 'Clark', 'Sales');
-- INSERT INTO EMPLOYEE VALUES (0002, 'Dave', 'Accounting');
-- INSERT INTO EMPLOYEE VALUES (0003, 'Ava', 'Sales');

-- -- fetch 
-- SELECT * FROM EMPLOYEE WHERE dept = 'Sales';

CREATE TABLE Worker (
	WORKER_ID INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
	FIRST_NAME CHAR(25),
	LAST_NAME CHAR(25),
	SALARY INT(15),
	JOINING_DATE DATETIME,
	DEPARTMENT CHAR(25)
);

INSERT INTO Worker 
	(WORKER_ID, FIRST_NAME, LAST_NAME, SALARY, JOINING_DATE, DEPARTMENT) VALUES
		(001, 'Monika', 'Arora', 100000, '14-02-20 09.00.00', 'HR'),
		(002, 'Niharika', 'Verma', 80000, '14-06-11 09.00.00', 'Admin'),
		(003, 'Vishal', 'Singhal', 300000, '14-02-20 09.00.00', 'HR'),
		(004, 'Amitabh', 'Singh', 500000, '14-02-20 09.00.00', 'Admin'),
		(005, 'Vivek', 'Bhati', 600000, '14-06-11 09.00.00', 'Admin'),
		(006, 'Vipul', 'Diwan', 200000, '14-06-11 09.00.00', 'Account'),
		(007, 'Satish', 'Kumar', 75000, '14-01-20 09.00.00', 'Account'),
		(008, 'Geetika', 'Chauhan', 90000, '14-04-11 09.00.00', 'Admin');
        
-- SELECT * FROM Title;

CREATE TABLE Bonus (
	WORKER_REF_ID INT,
	BONUS_AMOUNT INT(10),
	BONUS_DATE DATETIME,
	FOREIGN KEY (WORKER_REF_ID)
		REFERENCES Worker(WORKER_ID)
        ON DELETE CASCADE
);

INSERT INTO Bonus 
	(WORKER_REF_ID, BONUS_AMOUNT, BONUS_DATE) VALUES
		(001, 5000, '16-02-20'),
		(002, 3000, '16-06-11'),
		(003, 4000, '16-02-20'),
		(001, 4500, '16-02-20'),
		(002, 3500, '16-06-11');
        
CREATE TABLE Title (
	WORKER_REF_ID INT,
	WORKER_TITLE CHAR(25),
	AFFECTED_FROM DATETIME,
	FOREIGN KEY (WORKER_REF_ID)
		REFERENCES Worker(WORKER_ID)
        ON DELETE CASCADE
);

INSERT INTO Title 
	(WORKER_REF_ID, WORKER_TITLE, AFFECTED_FROM) VALUES
 (001, 'Manager', '2016-02-20 00:00:00'),
 (002, 'Executive', '2016-06-11 00:00:00'),
 (008, 'Executive', '2016-06-11 00:00:00'),
 (005, 'Manager', '2016-06-11 00:00:00'),
 (004, 'Asst. Manager', '2016-06-11 00:00:00'),
 (007, 'Executive', '2016-06-11 00:00:00'),
 (006, 'Lead', '2016-06-11 00:00:00'),
 (003, 'Lead', '2016-06-11 00:00:00');
 
 
-- select upper(first_name) AS WORKER_NAME from worker;
-- select distinct(DEPARTMENT) from worker;
-- select instr(first_name, 'b') from worker where first_name = 'Amitabh';
-- select distinct(DEPARTMENT), length(DEPARTMENT) from worker;
-- select replace(first_name, 'a', 'A') as name from worker;
-- select concat(first_name, ' ', LAST_NAME) as name from worker;
-- select * from worker order by first_name, DEPARTMENT desc;
-- select * from worker where first_name not in ('Vipul', 'Satish');
-- select * from worker where department = 'Admin';
-- select * from worker where first_name like "%a%";
-- select * from worker where first_name like '%h' and length(first_name) = 6;
-- select * from worker where SALARY in between 100000 and 500000;
-- select * from worker where YEAR(JOINING_DATE) = 2014 and MONTH(JOINING_DATE) = 02;
-- select concat(first_name, ' ', LAST_NAME), salary from worker where salary > 100000 and salary < 500000;
-- select department, count(department) from worker group by department order by count(department);
-- select * from worker where WORKER_ID in (select WORKER_REF_ID from Title where WORKER_TITLE = 'Manager');
-- select * from worker as w left join title as t on w.WORKER_ID = t.WORKER_REF_ID where t.WORKER_TITLE = 'Manager';
-- select WORKER_TITLE from title group by WORKER_TITLE;
-- select * from worker where mod(WORKER_ID, 2) != 0;
-- select curdate();
-- select now();
-- select salary from worker order by salary desc limit 5;
-- select salary from worker w1 where 4 = (SELECT COUNT(DISTINCT (salary)) from worker w2 where w2.salary >= w1.salary);

-- select salary from worker w1 where 5 = (select count(DISTINCT(salary)) from worker w2 where w2.salary >= w1.salary);
select count(salary) from worker group by salary;

created 1 year ago

MySQL online editor

Write, Run & Share MySQL queries online using OneCompiler's MySQL online editor and compiler for free. It's one of the robust, feature-rich online editor and compiler for MySQL. Getting started with the OneCompiler's MySQL editor is really simple and pretty fast. The editor shows sample boilerplate code when you choose language as 'MySQL' and start writing queries to learn and test online without worrying about tedious process of installation.

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;