-- Create a table called client with the following columns: -- id- an auto-incrementing integer which is the primary key, size 11 -- first_name- a varchar with a maximum length of 255 characters, cannot be null -- last_name- a varchar with a maximum length of 255 characters, cannot be null -- email- a varchar with a maximum length of 255 characters, cannot be null -- The combination of the first_nameand last_name must be unique in this table. Name this constraint as full_name CREATE TABLE client ( id INT(11) NOT NULL AUTO_INCREMENT, first_name VARCHAR(255) NOT NULL, last_name VARCHAR(255) NOT NULL, email VARCHAR(255) NOT NULL, CONSTRAINT full_name UNIQUE (first_name, last_name), PRIMARY KEY (id) ); -- Create a table called employee with the following columns: -- id- an auto-incrementing integer which is the primary key, size 11 -- first_name- a varchar of maximum length 255, cannot be null -- last_name- a varchar of maximum length 255, cannot be null -- start_date- a date, cannot be null -- email- a varchar with a maximum length of 255 characters, cannot be null -- The combination of the first_nameand last_name must be unique in this table. Name this constraint as full_name CREATE TABLE employee ( id INT(11) NOT NULL AUTO_INCREMENT, first_name VARCHAR(255) NOT NULL, last_name VARCHAR(255) NOT NULL, start_date DATE NOT NULL, email VARCHAR(255) NOT NULL, CONSTRAINT full_name UNIQUE (first_name, last_name), PRIMARY KEY (id) ); -- Create a table called project with the following columns: -- id- an auto-incrementing integer which is the primary key, size 11 -- title- a varchar of maximum length 255, cannot be null -- comments- a text column -- cid- an integer which is a foreign key reference to the client table -- The project titlemust be unique in this table CREATE TABLE project ( id INT(11) NOT NULL AUTO_INCREMENT, title VARCHAR(255) NOT NULL UNIQUE, comments TEXT, cid INT NOT NULL, FOREIGN KEY (cid) REFERENCES client(id), PRIMARY KEY (id) ); -- Create a table called works_on representing a many-to-many relationship between employees and projects, with the following properties: -- pid- an integer which is a foreign key reference to the project table -- eid- an integer which is a foreign key reference to the employee table -- due_date- a date, not null -- The primary key is a combination of eid and pid CREATE TABLE works_on ( pid INT NOT NULL, eid INT NOT NULL, due_date DATE NOT NULL, PRIMARY KEY (eid, pid), FOREIGN KEY (pid) REFERENCES project(id), FOREIGN KEY (eid) REFERENCES employee(id) ); -- Insert the following into the client table: -- First Name | Last Name | Email -- Sara | Smith | [email protected] -- Miguel | Cabrera | [email protected] -- Bo | Chan'g | [email protected] INSERT INTO client (first_name, last_name, email) VALUES ("Sara", "Smith", "[email protected]"), ("Miguel", "Cabrera", "[email protected]"), ("Bo", "Chan'g", "[email protected]"); -- Insert the following into the employee table: -- First name | Last Name | Start Date | Email -- Ananya | Jaiswal | 2008-04-10 | [email protected] -- Michael | Fern | 2015-07-19 | [email protected] -- Abdul | Rehman | 2018-02-27 | [email protected] INSERT INTO employee (first_name, last_name, start_date, email) VALUES ("Ananya", "Jaiswal", "2008-04-10", "[email protected]"), ("Michael", "Fern", "2015-07-19", "[email protected]"), ("Abdul", "Rehman", "2018-02-27", "[email protected]"); -- Insert the following project instances into the project table -- (you should use a subquery to set up foreign key references AND not hard-coded numbers): -- cid | title | comments -- r to smiths | Diamond | Should be done by Jan 2019 -- r to bochang | Chan'g | Ongoing maintenance -- r to mc | The Robinson Project | NULL INSERT INTO project (cid, title, comments) VALUES ((SELECT id FROM client WHERE first_name = 'Sara' AND last_name = 'Smith'), 'Diamond', 'Should be done by Jan 2019'), ((SELECT id FROM client WHERE first_name = 'Bo' AND last_name = "Chan'g"), "Chan'g", 'Ongoing maintenance'), ((SELECT id FROM client WHERE first_name = 'Miguel' AND last_name = 'Cabrera'), 'The Robinson Project', NULL); -- Insert the following into the works_on table. -- Again, your queries here should not have hard-coded integers for foreign keys. -- eid | pid | due_date -- Ananya Jaiswal | Chan'g | 2020-11-19 -- Michael Fern | The Robinson Project | 2020-12-05 -- Abdul Rehman | Diamond | 2021-01-01 INSERT INTO works_on (eid, pid, due_date) VALUES ((SELECT id FROM employee WHERE first_name = 'Ananya' AND last_name = 'Jaiswal'), (SELECT id FROM project WHERE title = "Chan'g"), '2020-11-19'), ((SELECT id FROM employee WHERE first_name = 'Michael' AND last_name = 'Fern'), (SELECT id FROM project WHERE title = 'The Robinson Project'), '2020-12-05'), ((SELECT id FROM employee WHERE first_name = 'Abdul' AND last_name = 'Rehman'), (SELECT id FROM project WHERE title = 'Diamond'), '2021-01-01'); describe client; describe employee; describe project; describe works_on; SELECT * FROM works_on; SELECT * FROM project;
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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;