mysql中column怎么用

SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'your_database_name' AND TABLE_NAME = 'your_table_name';

SELECT column1, column2
FROM your_table_name;

SELECT *
FROM your_table_name
ORDER BY column_name;

SELECT column_name, COUNT(*)
FROM your_table_name
GROUP BY column_name;

ALTER TABLE your_table_name
ADD COLUMN new_column_name data_type;

ALTER TABLE your_table_name
MODIFY COLUMN column_name new_data_type;

ALTER TABLE your_table_name
DROP COLUMN column_name;

-- 错误的列名
SELECT wrong_column_name
FROM your_table_name;

-- 正确的列名
SELECT correct_column_name
FROM your_table_name;

-- 检查表结构
DESCRIBE your_table_name;

-- 错误的数据类型修改
ALTER TABLE your_table_name
MODIFY COLUMN column_name VARCHAR(10);

-- 正确的数据类型修改
ALTER TABLE your_table_name
MODIFY COLUMN column_name VARCHAR(255);