Mysql database learning-2. database selection, creation, deletion, and change

Mysql database learning-2: database selection, creation, deletion, and change database selection. After the database is selected, you can still use the data tables in other databases by specifying [database. Data Table ].

use db_nameselect * from db_name.tbl_name

 

Show all databases

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

 

Display tables of the database feng

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

 

Database creation

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

 

Delete Database

drop database db_namedrop database db_name if not exists db_name

 

Database Modification

alter database db_name default character set  utf8                                          default collate  utf8_general_ci