mysql一些sql话语，查看表信息

mysql一些sql语句，查看表信息
查看表字段信息

SELECT  column_name AS `列名`,  data_type   AS `数据类型`,  character_maximum_length  AS `字符长度`, numeric_precision AS `数字长度`, numeric_scale AS `小数位数`, is_nullable AS `是否允许非空`,  CASE WHEN extra = 'auto_increment'    THEN 1 ELSE 0 END AS `是否自增`, column_default  AS  `默认值`,  column_comment  AS  `备注`FROM Information_schema.columnsWHERE  table_Name='test';

SHOW TABLE STATUS  FROM `database_name`;

SHOW TABLES   FROM `database_name`;