1. 查询当前所在数据库所有表信息
select table_name ,create_time , engine, table_collation, table_comment from information_schema.tables where table_schema = (select database()) order by create_time desc
select database()，当前数据库名称：
2.获取单个建表语句：
SHOW CREATE TABLE '表名'
3. 查询表中所有字段的属性（字段类型，名称，长度，描述，是否可空）（table_name=‘表名’）
select column_name, is_nullable, data_type, column_comment, column_key, extra from information_schema.columns
where table_name = 'test' and table_schema = (select database()) order by ordinal_position