增
create database dbname; # sql以分號結尾
create database if not exists dbname; # 判斷是否存在,若不存在則創建
create database dbname character set 字符集;#創建並指定字符集
CREATE TABLE TBNAME(
COLUMN1 字段類型,
COLUMN2 字段類型,
...
);
insert into tbname(字段名1, 字段名2, ...) values (值1, 值2, ...)
刪
DROP DATABASE DBNAME;
DROP TABLE TBNAME;
delete from tbname where 字段名=值;
truncate table tbname;
改
ALTER DATABASE DBNAME CHARACTER SET 字符集; # 修改數據庫字符集
#修改表名
RENAME TABLE TBNAME1 TO TBNAME1;
#修改列名
ALTER TABLE TBNAME CHANGE COLUMN COLUMN_NEW 類型;
#修改列類型
ALTER TABLE 表名 MODIFY 列名 新的類型;
#修改字符集
#增加列
alter table tbname add column_new 類型;
#刪除列
alter table tbname drop column_name;
update tbname set 字段名=值 where 字段名=值;
查
SHOW DATABASES; # 查看所有數據庫
USE DATABASE DBNAME; # 使用數據庫
select database(); # 查看當前所在庫
show tables; #查看當前已有表
desc tbname;
show create table tbname; #查看錶的字符集
SELECT * FROM TBNAME;
SELECT COLUMN1,COLUMN2 FROM TBNAME;
SELECT COLUMN AS 別名 FROM TBNAME;
SELECT DISTINCT COLUMN FROM TBNAME;
條件查詢
- and、or、not
- like (%、_)
- between
- order by
- limit
高級查詢