MySQL Slides

Chapter 7/1 Copyright © 2004

Database Processing: Fundamentals, Design, and Implementation, 9/e by David M. Kroenke

ADVANCED MYSQL



Review Relational Model Terminology Relation is a two-dimensional table Attributes are single valued Each attribute belongs to a domain

– A domain is a physical and logical description of permittable values

No two rows are identical Order is unimportant The row is called a tuple



Relational Algebra

Relational algebra defines a set of operators that may work on relations.

Recall that relations are simply data sets. As such, relational algebra deals with set theory.

The operators in relational algebra are very similar to traditional algebra except that they apply to sets.



Relational Algebra Operators

Relational algebra provides several operators:– Union– Difference– Intersection– Product– Projection– Selection– Join



Union Operator

The union operator adds tuples from one relation to another relation

A union operation will result in combined relation

This is similar to the logical operator ‘OR’



Union Operator

JUNIOR and HONOR-STUDENT relations and their union:

(a)Example of JUNIOR relation

(b)Example HONOR-STUDENT relation

(c) Union of JUNIOR and HONOR-STUDENT relations



Difference Operator

The difference operator produces a third relation that contains the tuples that appear in the first relation, but not the second

This is similar to a subtraction



Difference Operator

JUNIOR relation

HONOR-STUDENT relation

JUNIOR minus HONOR-STUDENT relation



Intersection Operator

An intersection operation will produce a third relation that contains the tuples that are common to the relations involved.

This is similar to the logical operator ‘AND’



Intersection Operator

JUNIOR relation

HONOR-STUDENT relation

Intersection of JUNIOR and HONOR-STUDENT relations



Product Operator

A product operator is a concatenation of every tuple in one relation with every tuple in a second relation

The resulting relation will have n x m tuples, where…

n = the number of tuples in the first relation andm = the number of tuples in the second relation

This is similar to multiplication



Projection Operator

A projection operation produces a second relation that is a subset of the first.

The subset is in terms of columns, not tuples

The resulting relation will contain a limited number of columns. However, every tuple will be listed.



Selection Operator

The selection operator is similar to the projection operator. It produces a second relation that is a subset of the first.

However, the selection operator produces a subset of tuples, not columns.

The resulting relation contains all columns, but only contains a portion of the tuples.



Join Operator

The join operator is a combination of the product, selection, and projection operators. There are several variations of the join operator…– Equijoin– Natural join– Outer join

• Left outer join• Right outer join



Data for Join Examples

SID Name Major GradeLevel

123 Jones History JR

158 Parks Math GR

271 Smith History JR

105 Anderson Management SN

StudentNumber ClassName PositionNumber

123 H350 1

105 BA490 3

123 B490 7



Join Examples

Equijoin

Natural Join

Left OuterJoin



Expressing Queries in Relational Algebra

1. What are the names of all students?

STUDENT [Name]

2. What are the student numbers of all students enrolled in a class?

ENROLLMENT [StudentNumber]



Expressing Queries in Relational Algebra3. What are the student numbers of all

students not enrolled in a class?STUDENT [SID] – ENROLLMENT

[StudentNumber]

4. What are the numbers of students enrolled in the class ‘BD445’?

ENROLLMENT WHERE ClassName = ‘BD445’[StudentNumber]




5. What are the names of the students enrolled in class ‘BD445’?

STUDENT JOIN (SID = StudentNumber) ENROLLMENT WHERE ClassName = ‘BD445’[STUDENT.Name]




6. What are the names and meeting times of ‘PARKS’ classes?

STUDENT WHERE Name = ‘PARKS’ JOIN (SID=StudentNumber) ENROLLMENT JOIN (ClassName = Name) CLASS

[CLASS.Name, Time]



Expressing Queries in Relational Algebra7. What are the grade levels and meeting

rooms of all students, including students not enrolled in a class?

STUDENT LEFT OUTER JOIN (SID = StudentNumber) ENROLLMENT JOIN (ClassName = Name) CLASS [GradeLevel, Room]



Summary of Relational Algebra Operators

Fundamentals, Design, and Implementation, 9/e

Using SQL in Applications



View Ridge Gallery

View Ridge Gallery is a small art gallery that has been in business for 30 years

It sells contemporary European and North American fine art

View Ridge has one owner, three salespeople, and two workers

View Ridge owns all of the art that it sells; it holds no items on a consignment basis



Application Requirements

View Ridge application requirements– Track customers and their artist interests– Record gallery's purchases– Record customers' art purchases– List the artists and works that have

appeared in the gallery– Report how fast an artist's works have

sold and at what margin– Show current inventory in a Web page



View Ridge Data Model



View Ridge Data Model

Problems: the keys for WORK and TRANSACTION are huge and the key for CUSTOMER is doubtful as many customers may not have an email address



Surrogate Key Database Design



Sample Values



Sample Values



Sample Values



Sample Values



Sample Values



CHECK CONSTRAINT

CHECK CONSTRAINT defines limits for column values

Two common uses– Specifying a range of allowed values– Specifying an enumerated list

CHECK constraints may be used – To compare the value of one column to another– To specify the format of column values– With subqueries



SQL Views

SQL view is a virtual table that is constructed from other tables or views

It has no data of its own, but obtains data from tables or other views

SELECT statements are used to define views– A view definition may not include an ORDER BY clause

SQL views are a subset of the external views– They can be used only for external views that involve

one multi-valued path through the schema



SQL Views

Views may be used to – Hide columns or rows– Show the results of computed columns– Hide complicated SQL statements – Provide a level of indirection between

application programs and tables– Assign different sets of processing

permissions to tables– Assign different sets of triggers



CREATE VIEW SYNTAX

CREATE [OR REPLACE]

ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}]

[DEFINER = { user | CURRENT_USER }] [SQL SECURITY { DEFINER | INVOKER }]

VIEW view_name [(column_list)]

AS select_statement [WITH [CASCADED | LOCAL] CHECK OPTION]



Example: CREATE VIEW

CREATE VIEW CustomerNameView AS

SELECT Name AS CustomerName

FROM CUSTOMER;

SELECT *

FROM CustomerNameView

ORDER BY CustomerName;



EXAMPLE







Updating Views

Views may or may not be updatable Rules for updating views are both

complicated and DBMS-specific



Updating Views

Guidelines:











ALTER VIEW SYNTAX

ALTER [ALGORITHM = {UNDEFINED |

MERGE | TEMPTABLE}] [DEFINER = { user | CURRENT_USER }] [SQL SECURITY { DEFINER | INVOKER }] VIEW view_name [(column_list)]

AS select_statement [WITH [CASCADED | LOCAL] CHECK OPTION]



CHECK TABLE

CHECK TABLE view_name: to check the validation of views



EXAMPLE



DROP VIEW SYNTAX

DROP VIEW [IF EXISTS] view_name [, view_name] ... [RESTRICT | CASCADE]





Importing and Exporting data

Using LOAD DATA INFILE statement to import data from files

Using SELECT … INTO OUTFILE statement to export data to files

Using mysqldump in command lines



Importing data from files

LOAD DATA [LOW_PRIORITY | CONCURRENT] [LOCAL] INFILE 'file_name' [REPLACE | IGNORE] INTO TABLE tbl_name [{FIELDS | COLUMNS} [TERMINATED BY 'string'] [[OPTIONALLY] ENCLOSED BY 'char'] [ESCAPED BY 'char'] ] [LINES [STARTING BY 'string'] [TERMINATED BY 'string'] ] [IGNORE number LINES] [(col_name,...)]



EXAMPLES



EXPORTING DATA

SELECT [ALL | DISTINCT | DISTINCTROW ] [HIGH_PRIORITY] [STRAIGHT_JOIN] [SQL_SMALL_RESULT] [SQL_BIG_RESULT] [SQL_BUFFER_RESULT] [SQL_CACHE | SQL_NO_CACHE] [SQL_CALC_FOUND_ROWS] select_expr [, select_expr ...] [FROM table_references [WHERE where_condition] [GROUP BY {col_name | expr | position} [ASC | DESC], ... [WITH ROLLUP]] [HAVING where_condition] [ORDER BY {col_name | expr | position} [ASC | DESC], ...] [LIMIT {[offset,] row_count | row_count OFFSET offset}] [PROCEDURE procedure_name(argument_list)] [INTO OUTFILE 'file_name' export_options | INTO DUMPFILE 'file_name' | INTO var_name [, var_name]] [FOR UPDATE | LOCK IN SHARE MODE]]



EXAMPLES





EXPORTING DATA WITH MYSQLDUMP

shell> mysqldump [options] db_name [tbl_name ...]

shell> mysqldump [options] --databases db_name ...

shell> mysqldump [options] --all-databases



EXAMPLE



EXAMPLE



EXAMPLE



RESTORE DATA



Embedding SQL In Program Code SQL can be embedded in triggers, stored

procedures, and program code Problem: assigning SQL table columns with

program variables Solution: object-oriented programming, PL/SQL Problem: paradigm mismatch between SQL and

application programming language– SQL statements return sets of rows; an applications work

on one row at a time

Solution: process the SQL results as pseudo-files



Triggers

A trigger is a stored program that is executed by the DBMS whenever a specified event occurs on a specified table or view

Three trigger types: BEFORE, INSTEAD OF, and AFTER– Each type can be declared for Insert, Update, and Delete– Resulting in a total of nine trigger types

Oracle supports all nine trigger types SQL Server supports six trigger types (only for

INSTEAD OF and AFTER triggers)



CREATE TRIGGERS

CREATE TRIGGER trigger_name

{BEFORE|AFTER}

{INSERT|UPDATE|DELETE}

ON table_name

FOR EACH ROW

trigger_statement



Firing Triggers

When a trigger is fired, the DBMS supplies– Old and new values for the update– New values for inserts– Old values for deletions

The way the values are supplied depends on the DBMS product

Trigger applications:– Checking validity (Figure 7-14)– Providing default values (Figure 7-15)– Updating views (Figure 7-16)– Enforcing referential integrity actions (Figure 7-17, 7-18)



EXAMPLES











DROP TRIGGER

DROP TRIGGER trigger_name





User Variables and Prepared Statements

User varibles Using prepared statements with

mysql



User Variable Syntax

SET @var_name = expr [, @var_name = expr] ...

User variables can be assigned a value from a limited set of data types: integer, decimal, floating-point, binary or nonbinary string, or NULL value



EXAMPLES



String operators



Read a file of maximum_allowed_package bytes (1GB)







Syntax

PREPARE stmt_name FROM preparable_stmt

EXECUTE stmt_name [USING @var_name [, @var_name] ...]

{DEALLOCATE | DROP} PREPARE stmt_name



Prepare statement

mysql> PREPARE stmt1 FROM 'SELECT SQRT(POW(?,2) + POW(?,2)) AS hethuctamgiacvuong';

mysql> SET @a = 3; mysql> SET @b = 4; mysql> EXECUTE stmt1 USING @a,

@b;











Drop Prepare



E-PROJECT

Nhom 1: Men (TL), Phu, Trong Nhom 2: Tu, Khai (TL), Quyet, Hien



Nội dung

Lựa chọn và giới thiệu chủ đề (có khảo sát thực tế)

Thiết kế cơ sở dữ liệu, quan hệ giữa các bảng (quan hệ các bảng được biểu diễn bằng sơ đồ)

Dữ liệu >=50 records Sử dụng View cho các truy vấn trên

nhiều bảng



Export kết quả ra file txt hoặc xls Sử dụng triggers kiểm soát nhập, xuất dữ

liệu Sử dụng các stored functions, routines Phân quyền người dùng (root,admin,users) Cho phép kết nối database server từ nhiều

ip khác nhau



Báo cáo

Thứ 7 (3/12/2011) : trình bày trên lớp File export (.txt, .xls),

file .word, .ppt, .sql



Stored Procedures

A stored procedure is a program that is stored within the database and is compiled when used– In Oracle, it can be written in PL/SQL or Java– In SQL Server, it can be written in TRANSACT-SQL

Stored procedures can receive input parameters and they can return results

Stored procedures can be called from– Programs written in standard languages, e.g., Java, C#– Scripting languages, e.g., JavaScript, VBScript– SQL command prompt, e.g., SQL Plus, Query Analyzer



Stored Procedure Advantages

Greater security as store procedures are always stored on the database server

Decreased network traffic SQL can be optimized by the DBMS

compiler Code sharing resulting in

– Less work– Standardized processing– Specialization among developers



Define Procedure Syntax

CREATE [DEFINER = { user | CURRENT_USER }] PROCEDURE sp_name ([proc_parameter[,...]]) [characteristic ...] routine_body



Define Function Syntax

CREATE [DEFINER = { user | CURRENT_USER }] FUNCTION sp_name ([func_parameter[,...]]) RETURNS type [characteristic ...] routine_body



Examples













IN and OUT



Declare statement

Used for declaring varibles, conditions …

Syntax:

DECLARE var_name data_type





Conditions and Handlers

Conditions may arise during stored program execution that require special handling, such as exiting the current program block or continuing execution. Handlers can be defined for general conditions such as warnings or exceptions, or for specific conditions such as a particular error code. Specific conditions can be assigned names and referred to that way in handlers.



Conditions Declare syntax

DECLARE condition_name CONDITION FOR condition_value condition_value: mysql_error_code | SQLSTATE [VALUE] sqlstate_value



EXAMPLE



Handlers Declare syntax

DECLARE handler_action HANDLER FOR condition_value [, condition_value] ... statement handler_action:

CONTINUE | EXIT | UNDO

condition_value:

mysql_error_code | SQLSTATE [VALUE] sqlstate_value | condition_name | SQLWARNING | NOT FOUND | SQLEXCEPTION







CURSORS

MySQL supports cursors inside stored programs. The syntax is as in embedded SQL. Cursors have these properties:

1. Asensitive: The server may or may not make a copy of its result table

2. Read only: Not updatable 3. Nonscrollable: Can be traversed

only in one direction and cannot skip rows Cursors must be declared before

declaring handlers and after declaring variables and conditions.



DECLARE cursor_name CURSOR FOR select_statement

OPEN cursor_name FETCH cursor_name INTO var_name

[, var_name] ... CLOSE cursor_name









Flow control

IF and CASE: conditional testing LOOP, REPEAT, WHILE: loops



IF search_condition THEN statement_list [ELSEIF search_condition THEN statement_list] ... [ELSE statement_list] END IF





CASE case_value

WHEN when_value

THEN statement_list

[WHEN when_value THEN statement_list] ...

[ELSE statement_list]

END CASE



Attention: Transfer of Control

LEAVE label: transfer to the end of the named construct

ITERATE label: transfer to the beginning of the named construct

Transfer of Control can be used with blocks and loops





[begin_label:] LOOP statement_list END LOOP [end_label]





[begin_label:] WHILE search_condition DO statement_list END WHILE [end_label]



[begin_label:] REPEAT statement_list UNTIL search_condition END REPEAT [end_label]



Drop Procedure, Functions

DROP PROCEDURE proc_name DROP FUNCTION func_name



Account Management Statements

CREATE user DROP user RENAME user GRANT syntax



CREATE USER syntax

CREATE USER user_specification [, user_specification] ... user_specification: user [IDENTIFIED BY [PASSWORD] 'password']



RENAME USER syntax

RENAME USER old_user TO new_user [, old_user TO new_user] ...



DROP USER syntax

DROP USER username





GRANT syntax

GRANT priv_type [(column_list)] [, priv_type [(column_list)]] ... ON [object_type] priv_level TO user_specification [, user_specification] ... [REQUIRE {NONE | ssl_option [[AND] ssl_option] ...}] [WITH with_option ...]





Debugging MYSQL Applications

Interpret error messages Using SHOW WARNINGS and

SHOW ERRORS statements perror



SHOW WARNINGS statement



SHOW ERRORS statement



Using SQL In Application Code

SQL can be embedded in application programs

Several SQL statements need to be executed to populate an external view

The application program causes the statements to be executed and then displays the results of the query in the form’s grid controls



Using SQL In Application Code (cont.) The application program also processes

and coordinates user actions on a form, including– Populating a drop-down list box– Making the appropriate changes to foreign keys

to create record relationships The particulars by which SQL code is

inserted into applications depend on the language and data-manipulation methodology used

Fundamentals, Design, and Implementation, 9/e

ReviewIntroduction to MySQL



More features

Cross-database joins Outer joins API: C/C++, Eiffel, Java, PHP, Perl,

Python, TCL Runs on Windows, UNIX, and Mac High performance



SQL syntax

CREATE TABLE people (name CHAR(10)) INSERT INTO people VALUES (‘Joe’) SELECT name FROM people WHERE

name like ‘J%’



SQL commands

SHOW DATABASES SHOW TABLES Data types: INT, REAL, CHAR(l),

VARCHAR(l), TEXT(l), DATE, TIME ALTER TABLE mytable MODIFY

mycolumn TEXT(100) ENUM(‘cat’,’dog’,’rabbit’,’pig’)



SQL commands

CREATE DATABASE dbname CREATE TABLE tname (id NOT

NULL PRIMARY KEY AUTO_INCREMENT)

CREATE INDEX part_of_name ON customer (name(10))

INSERT INTO tname (c1, …, cn) values (v1, …, vn)



JOINs and ALIASing

SELECT book.title, author.nameFROM author, book

WHERE books.author = author.id

SELECT very_long_column_name AS col FROM tname WHERE col=‘5’



Loading text files

Comma-separated files (*.csv) LOAD DATA LOCAL INFILE

"whatever.csv" INTO TABLE tname



Aggregate queries

SELECT position FROM people GROUP by position

SELECT position, AVG (salary) FROM people GROUP BY position HAVING AVG (salary) > 50000.00



Full text search

CREATE TABLE WebCache (url VARCHAR (255) NOT NULL PRIMARY KEY,ptext TEXT NOT NULL,FULLTEXT (ptext));

INSERT INTO WebCache (url, ptext) VALUES (‘index.html’, ‘Welcome to the University of Michigan’);

SELECT url from WebCache WHERE MATCH (ptext) against (‘Michigan’);



Advanced features

Transactions Table locking Functions Unions Outer joins



Installing MySQL on Windows

http://www.mysql.com/products/mysql/

http://www.webdevelopersnotes.com/tutorials/sql/index.php3



Useful pointers

Small example: http://www.itl.nist.gov/div897/ctg/dm/sql_examples.htm

MySQL documentation:http://www.mysql.com/doc/en/index.html

(official) MySQL tutorial:http://www.mysql.com/doc/en/Tutorial.html

Online, interactive tutorials:http://sqlzoo.net/http://sql.grussell.org/



http://www.itl.nist.gov/div897/ctg/dm/sql_examples.htm

use test;

CREATE TABLE STATION

(ID INTEGER PRIMARY KEY,

CITY CHAR(20),

STATE CHAR(2),

LAT_N REAL,

LONG_W REAL);

DESCRIBE STATION;

INSERT INTO STATION VALUES (13, 'Phoenix', 'AZ', 33, 112);

INSERT INTO STATION VALUES (44, 'Denver', 'CO', 40, 105);

INSERT INTO STATION VALUES (66, 'Caribou', 'ME', 47, 68);

SELECT * FROM STATION;

SELECT * FROM STATION

WHERE LAT_N > 39.7;



SELECT ID, CITY, STATE FROM STATION; ID CITY STATE ;

SELECT ID, CITY, STATE FROM STATION

WHERE LAT_N > 39.7;

CREATE TABLE STATS

(ID INTEGER REFERENCES STATION(ID),

MONTH INTEGER CHECK (MONTH BETWEEN 1 AND 12),

TEMP_F REAL CHECK (TEMP_F BETWEEN -80 AND 150),

RAIN_I REAL CHECK (RAIN_I BETWEEN 0 AND 100),

PRIMARY KEY (ID, MONTH));

INSERT INTO STATS VALUES (13, 1, 57.4, 0.31);






SELECT * FROM STATS;



SELECT * FROM STATION, STATS

WHERE STATION.ID = STATS.ID;

SELECT MONTH, ID, RAIN_I, TEMP_F

FROM STATS

ORDER BY MONTH, RAIN_I DESC;

SELECT LAT_N, CITY, TEMP_F

FROM STATS, STATION

WHERE MONTH = 7

AND STATS.ID = STATION.ID

ORDER BY TEMP_F;

SELECT MAX(TEMP_F), MIN(TEMP_F), AVG(RAIN_I), ID

FROM STATS

GROUP BY ID;

SELECT * FROM STATION

WHERE 50 < (SELECT AVG(TEMP_F) FROM STATS

WHERE STATION.ID = STATS.ID);



CREATE VIEW METRIC_STATS (ID, MONTH, TEMP_C, RAIN_C) AS

SELECT ID,

MONTH,

(TEMP_F - 32) * 5 /9,

RAIN_I * 0.3937

FROM STATS;

SELECT * FROM METRIC_STATS;

SELECT * FROM METRIC_STATS

WHERE TEMP_C < 0 AND MONTH = 1

ORDER BY RAIN_C;

UPDATE STATS SET RAIN_I = RAIN_I + 0.01;


UPDATE STATS SET TEMP_F = 74.9

WHERE ID = 44

AND MONTH = 7;




COMMIT WORK;

UPDATE STATS SET RAIN_I = 4.50

WHERE ID = 44;


ROLLBACK WORK;


UPDATE STATS SET RAIN_I = 4.50

WHERE ID = 44

AND MONTH = 7;

COMMIT WORK;




DELETE FROM STATS

WHERE MONTH = 7

OR ID IN (SELECT ID FROM STATION

WHERE LONG_W < 90);

DELETE FROM STATION WHERE LONG_W < 90;

COMMIT WORK;

SELECT * FROM STATION;


SELECT * FROM METRIC_STATS;



http://www.mysql.com/doc/en/Tutorial.html

CREATE TABLE animals (

id MEDIUMINT NOT NULL AUTO_INCREMENT,

name CHAR(30) NOT NULL,

PRIMARY KEY (id)

);

INSERT INTO animals (name) VALUES ("dog"),("cat"),("penguin"),

("lax"),("whale"),("ostrich");

SELECT * FROM animals;

CREATE TABLE shop (

article INT(4) UNSIGNED ZEROFILL DEFAULT '0000' NOT NULL,

dealer CHAR(20) DEFAULT '' NOT NULL,

price DOUBLE(16,2) DEFAULT '0.00' NOT NULL,

PRIMARY KEY(article, dealer));

INSERT INTO shop VALUES

(1,'A',3.45),(1,'B',3.99),(2,'A',10.99),(3,'B',1.45),(3,'C',1.69),

(3,'D',1.25),(4,'D',19.95);

SELECT * FROM shop;



CREATE TABLE articles (

id INT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,

title VARCHAR(200),

body TEXT,

FULLTEXT (title,body)

);

INSERT INTO articles VALUES

(NULL,'MySQL Tutorial', 'DBMS stands for DataBase ...'),

(NULL,'How To Use MySQL Efficiently', 'After you went through a ...'),

(NULL,'Optimizing MySQL','In this tutorial we will show ...'),

(NULL,'1001 MySQL Tricks','1. Never run mysqld as root. 2. ...'),

(NULL,'MySQL vs. YourSQL', 'In the following database comparison ...'),

(NULL,'MySQL Security', 'When configured properly, MySQL ...');

SELECT * FROM articles

WHERE MATCH (title,body) AGAINST ('database');



# What's the highest item number?

SELECT MAX(article) AS article FROM shop;

# Find number, dealer, and price of the most expensive article.

SELECT MAX(price) FROM shop;

SELECT article, dealer, price

FROM shop

WHERE price=19.95;

SELECT article, dealer, price

FROM shop

ORDER BY price DESC

LIMIT 1;

# What's the highest price per article?

SELECT article, MAX(price) AS price

FROM shop

GROUP BY article;



CREATE TEMPORARY TABLE tmp (

article INT(4) UNSIGNED ZEROFILL DEFAULT '0000' NOT NULL,

price DOUBLE(16,2) DEFAULT '0.00' NOT NULL);

LOCK TABLES shop READ;

INSERT INTO tmp SELECT article, MAX(price) FROM shop GROUP BY article;

SELECT shop.article, dealer, shop.price FROM shop, tmp

WHERE shop.article=tmp.article AND shop.price=tmp.price;

UNLOCK TABLES;

DROP TABLE tmp;

SELECT article,

SUBSTRING( MAX( CONCAT(LPAD(price,6,'0'),dealer) ), 7) AS

dealer,

0.00+LEFT( MAX( CONCAT(LPAD(price,6,'0'),dealer) ), 6) AS price

FROM shop

GROUP BY article;



# find the articles with the highest and lowest price

SELECT @min_price:=MIN(price),@max_price:=MAX(price) FROM shop;

SELECT * FROM shop WHERE price=@min_price OR price=@max_price;

# foreign keys

CREATE TABLE person (

id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT,

name CHAR(60) NOT NULL,

PRIMARY KEY (id)

);

CREATE TABLE shirt (

id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT,

style ENUM('t-shirt', 'polo', 'dress') NOT NULL,

color ENUM('red', 'blue', 'orange', 'white', 'black') NOT NULL,

owner SMALLINT UNSIGNED NOT NULL REFERENCES person(id),

PRIMARY KEY (id)

);



INSERT INTO person VALUES (NULL, 'Antonio Paz');

INSERT INTO shirt VALUES

(NULL, 'polo', 'blue', LAST_INSERT_ID()),

(NULL, 'dress', 'white', LAST_INSERT_ID()),

(NULL, 't-shirt', 'blue', LAST_INSERT_ID());

INSERT INTO person VALUES (NULL, 'Lilliana Angelovska');

INSERT INTO shirt VALUES

(NULL, 'dress', 'orange', LAST_INSERT_ID()),

(NULL, 'polo', 'red', LAST_INSERT_ID()),

(NULL, 'dress', 'blue', LAST_INSERT_ID()),

(NULL, 't-shirt', 'white', LAST_INSERT_ID());

SELECT * FROM person;

SELECT * FROM shirt;



SELECT s.* FROM person p, shirt s

WHERE p.name LIKE 'Lilliana%'

AND s.owner = p.id

AND s.color <> 'white';

# unions

select id, style from shirt where color = 'blue' union select id,

style from shirt where color = 'orange'

# visits per day

CREATE TABLE t1 (year YEAR(4), month INT(2) UNSIGNED ZEROFILL,

day INT(2) UNSIGNED ZEROFILL);

INSERT INTO t1 VALUES(2000,1,1),(2000,1,20),(2000,1,30),(2000,2,2),

(2000,2,23),(2000,2,23);

SELECT year,month,BIT_COUNT(BIT_OR(1<<day)) AS days FROM t1

GROUP BY year,month;



References

Bài giảng MySQL Ai-ti Aptech SQL applications Dragomir R. Radev

Fall 2005 http://dev.mysql.com/doc/refman/

5.5/en/

MySQL Slides

Documents

id smallint

unsigned zerofill

null primary

unsigned zerofill

updating views

application

shellgt

primary key