/*1.查询所有数据库*/
show databases;
/*2.查询所有数据表*/
select * from information_schema.tables where table_schema='world'
/*3.查询指定表的所有字段*/
select * from information_schema.columns
where table_schema='world'
and table_name='city'
show databases;
/*2.查询所有数据表*/
select * from information_schema.tables where table_schema='world'
/*3.查询指定表的所有字段*/
select * from information_schema.columns
where table_schema='world'
and table_name='city'
