 /*select char_length('hello');
select ascii('a');
select concat('hello',' ','world');
select concat_ws('#','hello','world');
select insert('hello world',6,2,' here');


create table employee(id int,name_e varchar(20));

insert into employee values(1,'sidhant');

select * from employee;*/

/*select lcase('ASDFGH');
select left ('sidhanth',4);
select locate('v','sidhanths');
select rpad('hello',15,'#');
select trim('   hi hello ');
select ceil(5.01);
select abs(-7);
select floor(7.0);
select max(1,3,4,55,666);*/
/*create table employees (id int, name varchar(25),sale int,extra int);
insert into employees values(4,'Catherine',25,null);

select * from employees;
select count(id),count(name),count(sale) from employees;

create table sales(id int, name varchar(15),sales int);
INSERT INTO sales (id, name, sales) VALUES (1, 'John', 100);
INSERT INTO sales (id, name, sales) VALUES (2, 'Sarah', 200);
INSERT INTO sales (id, name, sales) VALUES (3, 'Alex', 300);
INSERT INTO sales (id, name, sales) VALUES (4, 'John', 400);
INSERT INTO sales (id, name, sales) VALUES (5, 'Sarah', 500);

/*select name,group_concat(sales) from sales
group by name*/
/*select name, sum(sales) from sales group by name
having name='John';
select sum(sales) from sales;
select id,name,cast(sales as decimal(10,2)) as sales from sales;
select cast(12345 as decimal(10,2)) as decimal_value;

select cast(current_date as char) as date_string;
select current_date;

select cast('hello world' as char) as char_length;

select curdate();
select curtime();
select now();

select date_add(curdate(), interval 7 day);
select date_add(curdate(), interval 7 month);
select date_sub(curdate(), interval 7 day);
select date_sub(curdate(), interval -7 day);

select datediff('2022-01-01','2020-01-01');

select dayname(curdate());*/
/*
create table sales(id int, name varchar(15),sales int);
INSERT INTO sales (id, name, sales) VALUES (1, 'John', 100);
INSERT INTO sales (id, name, sales) VALUES (2, 'Sarah', 200);
INSERT INTO sales (id, name, sales) VALUES (3, 'Alex', 300);
INSERT INTO sales (id, name, sales) VALUES (4, 'John', 400);
INSERT INTO sales (id, name, sales) VALUES (5, 'Sarah', 500);
INSERT INTO sales (id, name, sales) VALUES (6, 'Sarah', 500);

select *,
dense_rank() over (order by sales asc) as d_rank_ ,
row_number() over (order by sales asc) as rownumber_ ,
dense_rank() over (order by sales asc) as rank_
from sales;

select name,sales,
        lead(sales,1) over (order by sales asc) as next_sale
        from sales;
        
select name,sales,
        lag(sales,1) over (order by sales asc) as next_sale
        from sales;
        
select *,
max(sales) over(partition by name)
as max_sales
from sales;

select *,
sum(sales) over(partition by name)
as sum_sal
from sales;
  */      
      
create table sales(id int, name varchar(15),sales int);
INSERT INTO sales (id, name, sales) VALUES (1, 'John', 100);
INSERT INTO sales (id, name, sales) VALUES (3, 'Sarah', 200);
INSERT INTO sales (id, name, sales) VALUES (2, 'Alex', 300);
INSERT INTO sales (id, name, sales) VALUES (40, 'John', 400);
INSERT INTO sales (id, name, sales) VALUES (5, 'Sarah', 500);
INSERT INTO sales (id, name, sales) VALUES (0, 'Sarah', 500);

create table sales1(id1 int, name1 varchar(15),sales1 int);
INSERT INTO sales1  VALUES (11, 'John1', 100);
INSERT INTO sales1  VALUES (33, 'Sarah1', 200);
INSERT INTO sales1  VALUES (2, 'Alex1', 300);
INSERT INTO sales1  VALUES (4040, 'John1', 400);
INSERT INTO sales1 VALUES (55, 'Sarah1', 500);
INSERT INTO sales1  VALUES (01, 'Sarah1', 500);
/*create view complex_view
as select sales.name,sales.id,sales1.id1 from sales cross join sales1;


select * from complex_view;*/
select * from sales;
select * from sales1;

select * from sales,sales1 where id in (select id1 from sales1);

select *,(select count(*) from sales as sal where sal.id=sall.id1) as count_p from sales1 as sall;

/*(create view sale_view
as select * from sales where id%2 = 0;

insert into sales values(1,'sid',900);

select * from sale_view;*/



/*alter table sales add primary key(id);*
create index id_index
on sales(id);
select * from sales;

INSERT INTO sales (id, name, sales) VALUES (4, 'Sarah', 200);

select * from sales;

created 2 years 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;