mysql数据库学习――2，数据库的选定，创建，删除和变更_MySQL

mysql数据库学习——2，数据库的选定，创建，删除和变更

数据库选定，数据库选定后依然可以使用其他数据库中的数据表，只要指定【数据库.数据表】即可

use db_nameselect * from db_name.tbl_name

显示所有数据库

mysql> select schema_name from information_schema.schemata;+--------------------+| schema_name        |+--------------------+| information_schema || feng               || mysql              |+--------------------+3 rows in set (0.11 sec)

显示属于数据库feng的表

mysql> select table_name from information_schema.tables where table_schema='feng';+------------+| table_name |+------------+| feng       |+------------+1 row in set (0.05 sec)

数据库创建

create database db_namecreate  database db_name if not exists db_namecreate  database db_name if not exists db_name  character set utf8 collate utf8_icelandic_cishow create database db_name/G

数据库删除

drop database db_namedrop database db_name if not exists db_name

数据库修改

alter database db_name default character set  utf8                                          default collate  utf8_general_ci