根据输入参数更改WHERE子句

import mysql.connector

def get_data_by_parameter(parameter):
    # 连接数据库
    conn = mysql.connector.connect(
        host="localhost",
        user="your_username",
        password="your_password",
        database="your_database"
    )
    cursor = conn.cursor()

    # 根据不同的输入参数构建不同的WHERE子句
    if parameter == "A":
        where_clause = "column_name = 'value_A'"
    elif parameter == "B":
        where_clause = "column_name = 'value_B'"
    else:
        where_clause = ""

    # 构建查询语句
    query = "SELECT * FROM table_name"
    if where_clause:
        query += " WHERE " + where_clause

    # 执行查询
    cursor.execute(query)
    result = cursor.fetchall()

    # 关闭数据库连接
    cursor.close()
    conn.close()

    return result