1.从excel导入数据

在excel导入数据时要先在数据库中创建对应的数据库表

CREATE TABLE your_table_name (crawl_datetime DATE,url CHAR(255),company_name CHAR(255),company_size CHAR(255),company_type CHAR(255),job_type CHAR(255),job_name CHAR(255),edu CHAR(255),empltype CHAR(255),tag VARCHAR(255), -- 删除逗号salary CHAR(255),city CHAR(255),workingexp CHAR(255),resume_count SMALLINT,company_score DOUBLE, -- 删除长度work_place VARCHAR(255),require_content TEXT
);

接下来是操作的步骤

先选择导入向导，

 

然后选择excel

选择文件，选择需要导入的表

之后点击开始等待一会就结束了

2.尝试简单查询/复杂查询

#select COUNT(*) FROM 智联招聘
#select COUNT(*) FROM 智联招聘 WHERE crawl_datetime > '2018-12-28'; 
#select * FROM 智联招聘 UNION select * FROM 智联招聘 #14.07s
#select url as 地址 FROM 智联招聘

select url as 地址,crawl_datetime AS 时间,resume_count AS 申请人数 
FROM 智联招聘
ORDER BY resume_count DESC; #1.509S

3.在select中使用if/case语句（from、where中也可以）

select url as 地址,crawl_datetime AS 时间,resume_count AS 申请人数 
FROM 智联招聘
WHERE resume_count >= ALL (select resume_count FROM 智联招聘 WHERE crawl_datetime = '2018-12-29' 
)
ORDER BY resume_count DESC; #2.333S

4.创建视图

/*
CREATE VIEW 时间分类 AS
select job_name,CASE WHEN DAY(crawl_datetime) = 28 THEN 'good'ELSE 'bad'END 
from 智联招聘 #1.347s
*/#SELECT * from 时间分类 #1.348s

5.创建存储过程

DELIMITER $$
CREATE PROCEDURE get_job_name()
BEGINSELECT job_name FROM `智联招聘`;
END $$
DELIMITER ;CALL get_job_name();

6.存储过程中的本地变量

DROP PROCEDURE get_locak;
DELIMITER $$
CREATE DEFINER='sa'@localhost PROCEDURE get_locak(jobname VARCHAR(50),OUT tag2 VARCHAR(50),OUT edu2 VARCHAR(50)
)
BEGINSELECT tag,eduINTO tag2,edu2FROM `智联招聘` WHERE job_name = jobname;
END $$
DELIMITER ;
CALL get_locak('湖南业务代表', @tag, @edu);SELECT @tag AS tag, @edu AS edu;
#注意不要重名

7.创建函数

CREATE FUNCTION get_risk_factor2()
RETURNS INTEGER
READS SQL DATA
BEGINDECLARE risk_id DECIMAL(9,2) DEFAULT 0;-- 计算风险因素的逻辑-- 假设你有一个与该函数相关的数据表来获取风险因素-- 可以是一些计算，或者从其他地方获取的值-- 这里我只是简单地给 risk_id 赋值为 1，你需要根据实际情况进行修改SET risk_id = 1;-- 将风险因素乘以 5SET risk_id = risk_id * 5;-- 返回风险因素的值RETURN risk_id;
END;

8.创建触发器

CREATE TRIGGER 添加之前触发BEFORE INSERT ON `智联招聘`FOR EACH ROW
BEGININSERT INTO 实践触发器(content)VALUES (NOW());
END

9.创建事件

CREATE EVENT 每一分钟都添加
ON SCHEDULEEVERY 1 MINUTE
DO BEGININSERT INTO 实践事件(content)VALUES (NOW());
END;SHOW EVENTS LIKE '每一分钟%';
ALTER EVENT 每一分钟都添加 DISABLE;

10.创建事务

START TRANSACTION;SELECT * FROM `智联招聘`;COMMIT ;SHOW VARIABLES;

11.创建索引

EXPLAIN SELECT tag FROM `智联招聘` #查看
create INDEX 标签 on `智联招聘`(tag); #2.881
SELECT tag FROM `智联招聘` #0.008s #没有索引是1.303s
DROP INDEX 标签 on `智联招聘`;