查询多个MySQL不同大小的表以进行JSON输出

import json
import pymysql

# 连接到MySQL数据库
conn = pymysql.connect(host='localhost', user='username', password='password', db='database')
cursor = conn.cursor()

# 编写SQL查询语句
sql = """
SELECT * FROM table1
UNION ALL
SELECT * FROM table2
UNION ALL
SELECT * FROM table3
"""

# 执行SQL查询语句
cursor.execute(sql)

# 处理查询结果
results = cursor.fetchall()

# 转换为JSON格式
data = []
for row in results:
    data.append({
        'column1': row[0],
        'column2': row[1],
        # 添加其他列...
    })

json_data = json.dumps(data)

# 输出JSON数据
print(json_data)

# 关闭数据库连接
cursor.close()
conn.close()