查询mysql表结构，表注释，表主键，字段类型，字段长度等

select
    distinct t.TABLE_SCHEMA,
    t.TABLE_NAME,
    t.TABLE_COMMENT,
    t1.COLUMN_NAME,
    t1.COLUMN_TYPE,
    t1.IS_NULLABLE,
    t1.COLUMN_DEFAULT,
    t1.COLUMN_COMMENT,
    t1.COLUMN_KEY
from
    information_schema.`tables` t
inner join information_schema.`columns` t1 on
    t.TABLE_NAME = t1.TABLE_NAME
where
    t.TABLE_SCHEMA = database ()
    and t.TABLE_NAME = '{}'