MySQL基础

mysql> SHOW DATABASES; 查看现在有多少数据库
mysql> CREATE DATABASE abccs;
mysql> USE abccs
mysql> SHOW TABLES;
mysql> CREATE TABLE mytable (name VARCHAR(20), sex CHAR(1), birth DATE, birthaddr VARCHAR(20));
mysql> DESCRIBE mytable;
mysql> insert into mytable values ('abccs','f','1977-07-07','china');
mysql> load data local infile 'c://1.txt' into table mytable;//从一个文本中导入，用tab键分隔数据。
mysql> update mytable set birth='2007-06-07' where name='lqy';//修改记录
mysql> select * from mytable where name='lqy' and birthaddr='cz';
mysql> select * from mytable order by birth desc;//逆序
mysql> SELECT COUNT(*) FROM mytable; //计数非null
mysql> SELECT sex,count(*) FROM mytable GROUP BY sex;