 CREATE TABLE DATEANDTIME(
DATE_AND_TIME DATETIME
);

INSERT INTO DATEANDTIME VALUES ('2021-09-03 09:16:40'),
('2021-06-29 06:36:54'),
('2020-11-14 10:13:09'),
('2019-05-12 04:24:04'),
('2020-12-29 07:30:30'),
('2018-05-14 10:13:09'),
('2010-01-02 12:30:24');

-- METHODS IN DATE TIME
SELECT DATE_AND_TIME FROM DATEANDTIME;

SELECT YEAR(DATE_AND_TIME) AS YEAR FROM DATEANDTIME ORDER BY YEAR(DATE_AND_TIME) DESC;

SELECT DISTINCT YEAR(DATE_AND_TIME) AS YEAR FROM DATEANDTIME ORDER BY YEAR(DATE_AND_TIME) DESC;

SELECT MONTH(DATE_AND_TIME) AS MONTH FROM DATEANDTIME;

SELECT MONTH(DATE_AND_TIME) AS MONTH FROM DATEANDTIME GROUP BY MONTH(DATE_AND_TIME);

-- SELECT MONTH(DATE_AND_TIME) AS MONTH FROM DATEANDTIME GROUP BY MONTH(DATE_AND_TIME) HAVING MONTH(DATE_AND_TIME)<6;

SELECT DATE(DATE_AND_TIME) AS DATE FROM DATEANDTIME ORDER BY DATE(DATE_AND_TIME) DESC;

SELECT DAY(DATE_AND_TIME) AS DAY FROM DATEANDTIME;

SELECT HOUR(DATE_AND_TIME) AS HOUR FROM DATEANDTIME;

SELECT MINUTE(DATE_AND_TIME) AS MINUTE FROM DATEANDTIME;

SELECT SECOND(DATE_AND_TIME) AS SECOND FROM DATEANDTIME;

SELECT TIME(DATE_AND_TIME) AS TIME FROM DATEANDTIME;

SELECT TIMESTAMP(DATE_AND_TIME) AS TIMESTAMP FROM DATEANDTIME;

SELECT QUARTER(DATE_AND_TIME) AS QUARTER FROM DATEANDTIME;

-- ADDING DATE OR HOUR OR MINUTE WE USE DATE_ADD() FUNCTION
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL 3 DAY) FROM DATEANDTIME;
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL -4 HOUR) FROM DATEANDTIME;
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL 10 MINUTE) FROM DATEANDTIME;
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL 30 SECOND) FROM DATEANDTIME;
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL -1 MONTH) FROM DATEANDTIME;
SELECT DATE_ADD(DATE_AND_TIME,INTERVAL 2 YEAR) FROM DATEANDTIME;


SELECT CURDATE();

SELECT CURTIME();

-- SELECT DATATYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE='DT';

-- replace 3 arguments -> value,the substring that needed to be replaced,the string to which it should be replaced ///substring ->string,  first index to last index   
SELECT REPLACE(SUBSTRING('2021-06-29T06:36:54Z', 1, 11), 'T' ,' '),REPLACE(SUBSTRING('2021-06-29T06:36:54Z', 12, 20), 'Z', ' ');

CREATE TABLE DAY(
DATETIME VARCHAR(21)
);

INSERT INTO DAY VALUES('2023-09-07T10:09:09Z');
SELECT * FROM DAY;

-- 1ST EXAMPLE IN CDP
-- (2021-11-24T22:25:55Z --> 2021-11-24 22:25:55)
SELECT REPLACE(SUBSTRING(DATETIME, 1, 11), 'T' ,' '),REPLACE(SUBSTRING(DATETIME, 12, 20), 'Z', ' ') FROM DAY;



CREATE TABLE DT(
DATES DATE,
TIMES TIME
);
INSERT INTO DT VALUES('2021-09-03',' 09:16:40'),
('2021-06-29 ','06:36:54'),
('2020-11-14 ','10:13:09'),
('2019-05-12 ','04:24:04'),
('2020-12-29 ','07:30:30'),
('2018-05-14 ','10:13:09'),
('2010-01-02 ','12:30:24');

SELECT * FROM DT;

-- IF WE HAVE BOTH DATE AND TIME COLUMN WE CANCATENATE OR WE CAN USE TIMESTAMP MEHTOD FOR GETTING TIMESTAMP
SELECT TIMESTAMP(DATES,TIMES) AS TIMESTAMP FROM DT;

SELECT CONCAT(DATES,' ',TIMES) AS TIMESTAMP FROM DT;

-- DATE_FORMAT(DATE_PARSE(lastupdatedatetime,'%m/%d/%Y'),'%Y-%m-%d %H:%i:%s') AS last_updatedate_time
-- SELECT DATE_FORMAT(DATE_PARSE(DATES,'%M/%D/%Y'),' %Y/%D/%M %H:%I:%S') AS TIMESTAMP FROM DT;
-- SELECT REPLACE(DATES,'%M/%D/%Y',' %Y/%D/%M %H:%I:%S') FROM DT;


-- FOR GETTING DATE WITH TIMESTAMP IF WE DONT HAVE TIME COLUMN (2021-09-03 TO 2021-09-03 00:00:00)
SELECT DATE_FORMAT(DATES, '%Y/%d/%m %H:%i:%s') FROM DT;

SELECT TIMESTAMP(DATES) FROM DT;




CREATE TABLE DT1(
DATES VARCHAR(20)
);

INSERT INTO DT1 VALUES ('04/09/2023');

select * from DT1;

SELECT DATE_FORMAT(DATES,'%Y/%d/%m %h:%i:%s') FROM DT1;


-- 04/09/2023 TO 2021-09-04 WE USE STR_TO_DATE METHOD
SELECT STR_TO_DATE(DATES,'%d/%m/%Y') FROM DT1;

-- 3RD EXAMPLE IN CDP 
-- 04/09/2023 TO 2023/04/09 00:00:00
SELECT DATE_FORMAT(STR_TO_DATE(DATES,'%d/%m/%Y'),'%Y/%d/%m %H:%i:%s') FROM DT1;





-- 2ND EXAMPLE IN CDP
-- (12/31/2015 4:29:53 PM --> 2015-12-31 04:29:53)
SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(STR_TO_DATE('2011-12-21 02:20pm', '%Y-%m-%d %h:%i%p')));

SELECT STR_TO_DATE('2011-12-21 02:20 pm', '%Y-%m-%d %h:%i%p');
SELECT STR_TO_DATE('2011-12-21T02:20:09 PM', '%Y-%m-%d %h:%i%p');

CREATE TABLE DT2(
DATETIME VARCHAR(25)
);

SELECT convert(DATETIME,'21-02-2012 6:10:00 PM',105)
SELECT
   CAST('02-21-2012 6:10:00 PM' AS DATETIME2),    
   CAST('01-01-2012 12:00:00 AM' AS DATETIME2)


INSERT INTO DT2 VALUES('12/31/2015',' 4:29:53 PM');

SELECT * FROM DT2;

-- SELECT DATE_FORMAT(SUBSTRING(DATES,1,11),'%Y/%m/%d %H:%i:%s') FROM DT2;

-- SELECT DATE(SUBSTRING(DATES,1,11)) FROM DT2;
SELECT DATE(DATES),TIME(TIME) FROM DT2;
SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(
    STR_TO_DATE(DATES, '%Y-%m-%d %h:%i%p'))
) FROM DT2;

SELECT STR_TO_DATE(DATES, '%Y-%m-%d %h:%i%p') FROM DT2;

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;