根据创建帖子的用户将帖子分组

# 示例帖子数据
posts = [
    {"user_id": 1, "content": "Hello World!"},
    {"user_id": 2, "content": "How are you?"},
    {"user_id": 1, "content": "Nice to meet you."},
    {"user_id": 3, "content": "What's up?"},
    {"user_id": 2, "content": "Goodbye!"}
]

# 按用户ID分组
grouped_posts = {}
for post in posts:
    user_id = post["user_id"]
    if user_id not in grouped_posts:
        grouped_posts[user_id] = []
    grouped_posts[user_id].append(post)

print(grouped_posts)

{
    1: [
        {"user_id": 1, "content": "Hello World!"},
        {"user_id": 1, "content": "Nice to meet you."}
    ],
    2: [
        {"user_id": 2, "content": "How are you?"},
        {"user_id": 2, "content": "Goodbye!"}
    ],
    3: [
        {"user_id": 3, "content": "What's up?"}
    ]
}

SELECT user_id, COUNT(*) AS post_count
FROM posts
GROUP BY user_id;