MySQL 实用CURD语句

查看所有表信息

SELECT
	* 
FROM
	information_schema.TABLES 
WHERE
	TABLE_SCHEMA = '数据库名'

查看各个表数据量

SELECT
	table_name,
	table_rows 
FROM
	information_schema.TABLES 
WHERE
	TABLE_SCHEMA = '数据库名' 
ORDER BY
	table_rows DESC;

查询数据库中包含某字段的所有表

SELECT
	TABLE_NAME,
	TABLE_SCHEMA,
	ORDINAL_POSITION,
	COLUMN_NAME,
	DATA_TYPE,
	CHARACTER_OCTET_LENGTH,
	COLUMN_KEY,
	EXTRA,
	IS_NULLABLE,
	CHARACTER_SET_NAME,
	COLUMN_DEFAULT,
	COLUMN_COMMENT 
FROM
	information_schema.COLUMNS 
WHERE
	TABLE_SCHEMA = '数据库名' 
	AND COLUMN_NAME = '字段名'

查询表字段名称和类型

SELECT
	column_name,
	column_comment,
	data_type 
FROM
	information_schema.COLUMNS 
WHERE
	table_name = '表名' 
	AND table_schema = '数据库名'

指定列追加字符

1	update pearl set 字段名=concat(字段名,"追加字符")

在一些已存在的记录中，追加相同的字符并修改。