PostgreSQL使用SQL实现俄罗斯方块的示例

1. 先安装一个PostgreSQL数据库
[postgres@pghost ~]$psql
psql (15.8)
2.安装 psycopg2
yum install postgresql-devel python3-devel
yum install -y python3-psycopg2
pip3 install psycopg2
pip3 install psycopg2-binary
3.游戏代码克隆
git clone https://github.com/nuno-faria/tetris-sql
chmod +x ./tetris-sql/input.py

1.本地运行 Python
python3 input.py \
[-h] [-H HOST] [-P PORT] \
[-d DB] [-u USER] [-p PASSWORD]
2.另一个终端运行以下查询
psql -U postgres -f tetris-sql/game.sql
说明：
game.sql 用于实现游戏逻辑，主要涉及通用表表达式（CTE）实现游戏循环；
input.py 用于捕获键盘输入。

CREATE TRIGGER encrypt_phone BEFORE INSERT ON users
FOR EACH ROW EXECUTE FUNCTION encrypt_data();

CREATE OR REPLACE FUNCTION clean_old_logs()
RETURNS VOID AS $$
BEGIN
   DELETE FROM logs WHERE created_at < NOW() - INTERVAL '30 days';
END;
$$ LANGUAGE plpgsql;
-- 每天凌晨执行
SELECT cron.schedule('0 0 * * *', 'SELECT clean_old_logs()');

CREATE OR REPLACE FUNCTION migrate_legacy_data()
RETURNS VOID AS $$
DECLARE
   batch_size INT := 1000;
   c CURSOR FOR SELECT * FROM legacy_table;
   r RECORD;
BEGIN
   OPEN c;
   LOOP
      FETCH c INTO r;
      EXIT WHEN NOT FOUND;
      INSERT INTO new_table 
      VALUES (r.id, transform_data(r.raw_content));
      IF (count % batch_size = 0) THEN COMMIT; END IF;
   END LOOP;
   CLOSE c;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE PROCEDURE backup_table(
    table_name TEXT, 
    file_path TEXT DEFAULT '/tmp/backup/'
) 
LANGUAGE plpgsql 
AS $$
DECLARE
    full_path TEXT;
    backup_cmd TEXT;
    file_suffix TEXT := to_char(CURRENT_TIMESTAMP, 'YYYYMMDD_HH24MISS');
BEGIN
    -- 验证表是否存在[7](@ref)
    IF NOT EXISTS (
        SELECT 1 FROM information_schema.tables 
        WHERE table_name = $1 
          AND table_schema = 'public'
    ) THEN
        RAISE EXCEPTION 'Table % does not exist', table_name;
    END IF;
    -- 生成带时间戳的文件路径
    full_path := file_path || table_name || '_' || file_suffix || '.csv';
    -- 构建COPY命令（自动处理列名）[6](@ref)
    backup_cmd := format(
        'COPY (SELECT * FROM %I) TO %L WITH (FORMAT CSV, HEADER, ENCODING ''UTF8'')', 
        table_name, 
        full_path
    );
    -- 执行备份命令
    BEGIN
        EXECUTE backup_cmd;
        RAISE NOTICE 'Table % backed up to %', table_name, full_path;
    EXCEPTION 
        WHEN insufficient_privilege THEN
            RAISE EXCEPTION 'Permission denied for path: %', file_path;
        WHEN others THEN
            RAISE EXCEPTION 'Backup failed: %', SQLERRM;
    END;
END;
$$;