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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
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