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MySQL周阳老师的建表语句
第13节相关SQL语句：
CREATE TABLE `tbl_emp` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(20) DEFAULT NULL,
`deptId` int(11) DEFAULT NULL,
PRIMARY KEY (`id`) ,
KEY `fk_dept_id`(`deptId`)
)ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8;
CREATE TABLE `tbl_dept` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`deptName` varchar(30) DEFAULT NULL,
`locAdd` varchar(40) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8;
INSERT INTO tbl_dept(deptName,locAdd) VALUES('RD',11);
INSERT INTO tbl_dept(deptName,locAdd) VALUES('HR',12);
INSERT INTO tbl_dept(deptName,locAdd) VALUES('MK',13);
INSERT INTO tbl_dept(deptName,locAdd) VALUES('MIS',14);
INSERT INTO tbl_dept(deptName,locAdd) VALUES('FD',15);
INSERT INTO tbl_emp(NAME,deptId) VALUES('z3',1);
INSERT INTO tbl_emp(NAME,deptId) VALUES('z4',1);
INSERT INTO tbl_emp(NAME,deptId) VALUES('z5',1);
INSERT INTO tbl_emp(NAME,deptId) VALUES('w5',2);
INSERT INTO tbl_emp(NAME,deptId) VALUES('w6',2);
INSERT INTO tbl_emp(NAME,deptId) VALUES('s7',3);
INSERT INTO tbl_emp(NAME,deptId) VALUES('s8',4);
INSERT INTO tbl_emp(NAME,deptId) VALUES('s9',51);
第31节-单表分析
CREATE TABLE IF NOT EXISTS `article`(
`id` INT(10) UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT,
`author_id` INT (10) UNSIGNED NOT NULL,
`category_id` INT(10) UNSIGNED NOT NULL ,
`views` INT(10) UNSIGNED NOT NULL ,
`comments` INT(10) UNSIGNED NOT NULL,
`title` VARBINARY(255) NOT NULL,
`content` TEXT NOT NULL
);
INSERT INTO `article`(`author_id`,`category_id` ,`views` ,`comments` ,`title` ,`content` )VALUES
(1,1,1,1,'1','1'),
(2,2,2,2,'2','2'),
(1,1,3,3,'3','3');
开始优化
explain select id from article where category_id = 1 and comments>1 order by views desc limit 1;
未使用索引之前：
image.png
第一次优化：创建索引
create index idx_article_ccv on article(category_id,comments,views);
使用索引之后：
image.png
如果将范围改为等于的情况下：
image.png
删除索引
drop index idx_article_ccv on article;
重新创建索引
create index idx_category_view on article (category_id,views);
image.png
P32 两表
-- 商品类别表
CREATE TABLE IF NOT EXISTS class (
id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
card INT(10) UNSIGNED NOT NULL,
PRIMARY KEY (id)
);
CREATE TABLE IF NOT EXISTS book (
bookid INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
card INT(10) UNSIGNED NOT NULL,
PRIMARY KEY ( bookid)
);
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO class(card) VALUES(FLOOR(1 + (RAND() * 20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO book(card)VALUES(FLOOR(1+(RAND()*20)));
分析
explain select * from class left join book on class.card = book.card;
image.png
创建book的索引
create index idx_b_card on book(card);
image.png
drop index idx_b_card on book;
创建class表的索引
create index idx_c_card on class;
image.png
索引需要加在被关联表中
第33节-三表
CREATE TABLE IF NOT EXISTS `phone`(
`phoneid` INT(10) UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT,
`card` INT (10) UNSIGNED NOT NULL
)ENGINE = INNODB;
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
INSERT INTO phone(card)VALUES(FLOOR(1+(RAND()*20)));
分析语句：
explain select * from class left join phone on class.card = phone.card left join book on book.card = class.card;
创建索引
create index idx_p_card on phone(card);
create index idx_b_card on book(card);
image.png
第34节
CREATE TABLE staffs(
id INT PRIMARY KEY AUTO_INCREMENT,
`name` VARCHAR(24)NOT NULL DEFAULT'' COMMENT'姓名',
`age` INT NOT NULL DEFAULT 0 COMMENT'年龄',
`pos` VARCHAR(20) NOT NULL DEFAULT'' COMMENT'职位',
`add_time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT'入职时间'
)CHARSET utf8 COMMENT'员工记录表';
INSERT INTO staffs(`name`,`age`,`pos`,`add_time`) VALUES('z3',22,'manager',NOW());
INSERT INTO staffs(`name`,`age`,`pos`,`add_time`) VALUES('July',23,'dev',NOW());
INSERT INTO staffs(`name`,`age`,`pos`,`add_time`) VALUES('2000',23,'dev',NOW());
SELECT * FROM staffs;
ALTER TABLE staffs ADD INDEX idx_staffs_nameAgePos(name,age,pos);
索引失效分析
explain select * from staffs where name='July';
image.png
explain select * from staffs where name='July' and age=25;
image.png
explain select * from staffs where name='July' and age=25 and pos='dev';
image.png
explain select * from staffs where age=25 and pos='dev';
image.png
第40节
CREATE TABLE `tbl_user`(
`id` INT(11) NOT NULL AUTO_INCREMENT,
`name` VARCHAR(20) DEFAULT NULL,
`age`INT(11) DEFAULT NULL,
`email` VARCHAR(20) DEFAULT NULL,
PRIMARY KEY(`id`)
)ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
INSERT INTO tbl_user(NAME ,age,email) VALUES('1aa1',21 ,'[email protected]');
INSERT INTO tbl_user(NAME ,age,email) VALUES('2aa2' ,222,'[email protected]');
INSERT INTO tbl_user(NAME ,age,email) VALUES('3aa3' ,265, '[email protected]');
INSERT INTO tbl_user(NAME, age,email) VALUES('4aa4',21,'[email protected]');
INSERT INTO tbl_user(NAME, age,email) VALUES('aa',121,'[email protected]');
44节
create table test03(
id int primary key not null auto_increment,
c1 char(10),
c2 char(10),
c3 char(10),
c4 char(10),
c5 char(10));
insert into test03(c1,c2,c3,c4,c5) values ('a1','a2','a3','a4','a5');
insert into test03(c1,c2,c3,c4,c5) values ('b1','b2','b3','b4','b5');
insert into test03(c1,c2,c3,c4,c5) values ('c1','c2','c3','c4','c5');
insert into test03(c1,c2,c3,c4,c5) values ('d1','d2','d3','d4','d5');
insert into test03(c1,c2,c3,c4,c5) values ('e1','e2','e3','e4','e5');
create index idx_test03_c1234 on test03(c1,c2,c3,c4);
50节
create database bigData;
use bigData;
#1建表dept
CREATE TABLE dept(
id INT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
deptno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
dname VARCHAR(20) NOT NULL DEFAULT '',
loc VARCHAR(13) NOT NULL DEFAULT ''
) ENGINE=INNODB DEFAULT CHARSET=GBK ;
#员工表
CREATE TABLE emp(
id INT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
empno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
ename VARCHAR(20) NOT NULL DEFAULT '',
job VARCHAR(9) NOT NULL DEFAULT '',
mgr MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
hiredate DATE NOT NULL,
sal DECIMAL(7,2) NOT NULL,
comm DECIMAL(7,2) NOT NULL,
deptno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0
)ENGINE=INNODB DEFAULT CHARSET=GBK ;
show variables like 'log_bin_trust_function_creators';
DELIMITER $$
CREATE FUNCTION rand_string(n INT) RETURNS VARCHAR(255)
BEGIN
DECLARE chars_str VARCHAR(100) DEFAULT 'abcdefghijklmnopqr stuvwxyzABCDEFJHIJKIMNOPQRSTUVWXYZ' ;
DECLARE return_str VARCHAR(255) DEFAULT '' ;
DECLARE i INT DEFAULT 0;
WHILE i调用存储过程
delimiter ;
call insert_dept(100,10);
第57节
create table test_innodb_lock (a int(11),b varchar(16))engine=innodb;
insert into test_innodb_lock values(1,'b2');
insert into test_innodb_lock values(3,'3');
insert into test_innodb_lock values(4, '4000');
insert into test_innodb_lock values(5,'5000');
insert into test_innodb_lock values(6,'6000');
insert into test_innodb_lock values(7,'7000');
insert into test_innodb_lock values(8,'8000');
insert into test_innodb_lock values(9,'9000');
insert into test_innodb_lock values(1,'b1');
create index test_innodb_a_ind on test_innodb_lock(a);
create index test_innodb_lock_b_ind on test_innodb_lock(b);