create table SALESMAN ( Salesman_id int, Name varchar(10), City varchar(10), Commission int, primary key(Salesman_id) ); create table CUSTOMER ( Customer_id int, Cust_name varchar(10), City varchar(10), Grade int, Salesman_id int, primary key (Customer_id), foreign key (Salesman_id) references SALESMAN (Salesman_id) on delete set NULL ); create table ORDERS ( Ord_no int, Purchase_amt int, Ord_date date, Customer_id int, Salesman_id int, primary key (Ord_no), foreign key (Customer_id) references CUSTOMER (customer_id) on delete cascade, foreign key (Salesman_id) references SALESMAN (salesman_id) on delete cascade ); insert into SALESMAN values (1000, 'joseph', 'mysore', '13'); insert into SALESMAN values (1001, 'girish', 'bangalore', '22'); insert into SALESMAN values (1002, 'mukund', 'mumbai', '16'); insert into SALESMAN values (1003, 'saurabh', 'delhi', '19'); insert into SALESMAN values (1004, 'srinivas', 'hydrabad', '23'); insert into SALESMAN values (1005, 'mohan', 'ranchi', '23'); insert into CUSTOMER values (1, 'sharal', 'hydrabad', 40, 1004); insert into CUSTOMER values (2, 'meenakshi', 'mangalore', 40, 1000); insert into CUSTOMER values (3, 'vikky', 'mumbai', 35, 1002); insert into CUSTOMER values (4, 'john', 'mumbai', 20, 1002); insert into CUSTOMER values (5, 'george', 'bangalore', 10, 1001); insert into CUSTOMER values (6, 'hevin', 'bangalore', 50, 1001); insert into CUSTOMER values (7, 'roshan', 'delhi', 45, 1003); insert into CUSTOMER values (8, 'vimala', 'chennai', 35, 1001); insert into CUSTOMER values (9, 'nakul', 'ayodhya', 15, 1005); insert into ORDERS values (111, 50000, '2017-01-04', 1, 1004); insert into ORDERS values (222, 45000, '2017-01-04', 2, 1000); insert into ORDERS values (333, 10000, '2017-02-05', 3, 1002); insert into ORDERS values (444, 35000, '2017-03-13', 4, 1003); insert into ORDERS values (555, 75000, '2017-03-14', 5, 1001); insert into ORDERS values (666, 25000, '2017-03-14', 6, 1004); insert into ORDERS values (777, 5000, '2017-06-27', 7, 1003); insert into ORDERS values (888, 52000, '2017-08-25', 8, 1001); insert into ORDERS values (991, 37000, '2017-08-25', 1, 1004); insert into ORDERS values (992, 29000, '2017-09-09', 2, 1000); insert into ORDERS values (993, 6000, '2017-09-09', 9, 1005); select * from SALESMAN; select * from CUSTOMER; select * from ORDERS; SELECT Grade, COUNT(DISTINCT Customer_id) as Total_Customers FROM CUSTOMER GROUP BY Grade HAVING Grade > (SELECT AVG(Grade) FROM CUSTOMER WHERE City = 'bangalore'); SELECT s.Salesman_id, s.Name FROM SALESMAN s WHERE (SELECT COUNT(*) FROM CUSTOMER c WHERE c.Salesman_id = s.Salesman_id) > 1; (select a.Salesman_id, a.Name, b.Cust_name, a.Commission, a.City from SALESMAN a, CUSTOMER b where a.City = b.City) UNION (select Salesman_id, Name, 'No Match', Commission, City from SALESMAN where NOT City = ANY (select City from CUSTOMER)) ORDER BY 2 DESC; create view TOPSALESMAN as select b.Ord_date,b.Purchase_amt,a.Salesman_id, a.Name from SALESMAN a, ORDERS b where a.Salesman_id = b.Salesman_id and b.Purchase_amt=(select MAX(c.Purchase_amt) from ORDERS c where b.Ord_date = c.Ord_date) ; select * from TOPSALESMAN; Delete from SALESMAN Where Salesman_Id=1000; select * from SALESMAN;
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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;