Asynchronous Operations

import mysql.connector.aio

async def connect(**kwargs) -> 'MySQLConnection':
    """
    Create async connection to MySQL server.
    
    Returns:
        MySQLConnection instance for async operations
    """
    pass

class MySQLConnection:
    """
    Async connection class with asyncio support.
    Provides non-blocking database operations using async/await.
    """
    
    def __init__(self, **kwargs) -> None:
        """Initialize async connection with configuration."""
        pass
    
    async def connect(self) -> None:
        """Establish async connection to MySQL server."""
        pass
    
    async def disconnect(self) -> None:
        """Close async connection to MySQL server."""
        pass
    
    async def close(self) -> None:
        """Close connection (alias for disconnect)."""
        pass
    
    def is_connected(self) -> bool:
        """Check if connection is active (non-blocking check)."""
        pass
    
    async def ping(self, reconnect: bool = False, attempts: int = 1, delay: int = 0) -> None:
        """Test connection to server asynchronously."""
        pass
    
    async def reconnect(self, attempts: int = 1, delay: int = 0) -> None:
        """Reconnect to MySQL server asynchronously."""
        pass
    
    def cursor(self, 
               buffered: Optional[bool] = None,
               raw: Optional[bool] = None,
               prepared: Optional[bool] = None,
               cursor_class: Optional[Type] = None,
               dictionary: Optional[bool] = None) -> 'MySQLCursor':
        """Create async cursor for executing SQL statements."""
        pass
    
    async def commit(self) -> None:
        """Commit current transaction asynchronously."""
        pass
    
    async def rollback(self) -> None:
        """Rollback current transaction asynchronously."""
        pass
    
    async def start_transaction(self, 
                               consistent_snapshot: bool = False,
                               isolation_level: Optional[str] = None,
                               readonly: Optional[bool] = None) -> None:
        """Start new transaction asynchronously."""
        pass
    
    @property
    def autocommit(self) -> bool:
        """Get autocommit mode status."""
        pass
    
    async def set_autocommit(self, value: bool) -> None:
        """Set autocommit mode asynchronously."""
        pass
    
    @property
    def database(self) -> str:
        """Get current database name."""
        pass
    
    async def set_database(self, value: str) -> None:
        """Change current database asynchronously."""
        pass
    
    @property
    def server_version(self) -> Tuple[int, int, int]:
        """Get MySQL server version tuple."""
        pass
    
    @property
    def connection_id(self) -> int:
        """Get MySQL connection ID."""
        pass
    
    @property
    def charset(self) -> str:
        """Get connection character set."""
        pass
    
    async def set_charset(self, value: str) -> None:
        """Set connection character set asynchronously."""
        pass
    
    async def cmd_query(self, query: Union[str, bytes]) -> Dict:
        """Execute query asynchronously and return raw result."""
        pass
    
    async def cmd_quit(self) -> bytes:
        """Send quit command to server asynchronously."""
        pass
    
    async def cmd_init_db(self, database: str) -> bytes:
        """Send init_db command to change database asynchronously."""
        pass
    
    async def cmd_refresh(self, options: int) -> bytes:
        """Send refresh command asynchronously."""
        pass
    
    async def cmd_statistics(self) -> Dict:
        """Get server statistics asynchronously."""
        pass
    
    async def cmd_ping(self) -> bytes:
        """Send ping command to server asynchronously."""
        pass
    
    async def reset_session(self, 
                           user_variables: Optional[Dict] = None, 
                           session_variables: Optional[Dict] = None) -> None:
        """Reset session to initial state asynchronously."""
        pass
    
    async def get_warnings(self, count: Optional[int] = None) -> List[Tuple]:
        """Get warning messages from last statement asynchronously."""
        pass
    
    @property
    def warning_count(self) -> int:
        """Get warning count from last statement."""
        pass
    
    @property
    def info_msg(self) -> Optional[str]:
        """Get info message from last statement."""
        pass
    
    @property
    def insert_id(self) -> int:
        """Get auto-generated ID from last INSERT."""
        pass
    
    @property
    def affected_rows(self) -> int:
        """Get affected row count from last statement."""
        pass
    
    @property
    def in_transaction(self) -> bool:
        """Check if connection is in transaction."""
        pass
    
    async def __aenter__(self) -> 'MySQLConnection':
        """Async context manager entry."""
        pass
    
    async def __aexit__(self, exc_type, exc_val, exc_tb) -> None:
        """Async context manager exit with automatic cleanup."""
        pass

class MySQLConnectionAbstract:
    """
    Abstract base class for async connections.
    Defines interface for async connection implementations.
    """
    pass

class MySQLCursor:
    """
    Async cursor for executing SQL statements.
    Provides non-blocking query execution and result fetching.
    """
    
    async def execute(self, operation: str, params: Optional[Union[Sequence, Dict]] = None, multi: bool = False) -> Optional[AsyncIterator]:
        """Execute SQL statement asynchronously with optional parameters."""
        pass
    
    async def executemany(self, operation: str, seq_params: Sequence[Union[Sequence, Dict]]) -> None:
        """Execute SQL statement multiple times asynchronously."""
        pass
    
    async def fetchone(self) -> Optional[Tuple]:
        """Fetch next row from result set asynchronously."""
        pass
    
    async def fetchmany(self, size: Optional[int] = None) -> List[Tuple]:
        """Fetch specified number of rows asynchronously."""
        pass
    
    async def fetchall(self) -> List[Tuple]:
        """Fetch all remaining rows asynchronously."""
        pass
    
    async def close(self) -> None:
        """Close cursor and free resources asynchronously."""
        pass
    
    async def callproc(self, procname: str, args: Sequence = ()) -> Optional[Dict]:
        """Call stored procedure asynchronously."""
        pass
    
    def stored_results(self) -> AsyncIterator['MySQLCursor']:
        """Return async iterator for stored procedure result sets."""
        pass
    
    async def nextset(self) -> Optional[bool]:
        """Skip to next result set asynchronously."""
        pass
    
    @property
    def description(self) -> Optional[List[Tuple]]:
        """Column metadata for last executed query."""
        pass
    
    @property 
    def rowcount(self) -> int:
        """Number of rows affected by last operation."""
        pass
    
    @property
    def lastrowid(self) -> Optional[int]:
        """Auto-generated ID from last INSERT operation."""
        pass
    
    @property
    def arraysize(self) -> int:
        """Default number of rows fetchmany() should return."""
        pass
    
    @arraysize.setter
    def arraysize(self, value: int) -> None:
        """Set default fetchmany() size."""
        pass
    
    @property
    def statement(self) -> Optional[str]:
        """Last executed SQL statement."""
        pass
    
    @property
    def with_rows(self) -> bool:
        """Whether last operation produced result rows."""
        pass
    
    @property
    def column_names(self) -> Tuple[str, ...]:
        """Column names from result set."""
        pass
    
    def __aiter__(self) -> 'MySQLCursor':
        """Make cursor async iterable over result rows."""
        pass
    
    async def __anext__(self) -> Tuple:
        """Get next row for async iteration."""
        pass
    
    async def __aenter__(self) -> 'MySQLCursor':
        """Async context manager entry."""
        pass
    
    async def __aexit__(self, exc_type, exc_val, exc_tb) -> None:
        """Async context manager exit with automatic cleanup."""
        pass

class MySQLConnectionPool:
    """
    Async connection pool manager.
    Manages pool of async database connections for efficient reuse.
    """
    
    def __init__(self, 
                 pool_name: Optional[str] = None,
                 pool_size: int = 5,
                 pool_reset_session: bool = True,
                 **kwargs) -> None:
        """Initialize async connection pool."""
        pass
    
    async def get_connection(self) -> 'PooledMySQLConnection':
        """Get connection from pool asynchronously."""
        pass
    
    async def add_connection(self, cnx: Optional['MySQLConnection'] = None) -> 'PooledMySQLConnection':
        """Add connection to pool asynchronously."""
        pass
    
    def set_config(self, **kwargs) -> None:
        """Update pool configuration."""
        pass
    
    async def close(self) -> None:
        """Close all connections in pool asynchronously."""
        pass
    
    @property
    def pool_name(self) -> str:
        """Pool name identifier."""
        pass
    
    @property
    def pool_size(self) -> int:
        """Maximum pool size."""
        pass

class PooledMySQLConnection:
    """
    Async pooled connection wrapper.
    Returns connection to pool on close in async context.
    """
    
    def __init__(self, pool: MySQLConnectionPool, cnx: 'MySQLConnection') -> None:
        """Initialize async pooled connection wrapper."""
        pass
    
    async def close(self) -> None:
        """Return connection to pool asynchronously."""
        pass
    
    @property
    def pool_name(self) -> str:
        """Name of the connection pool."""
        pass
    
    async def __aenter__(self) -> 'PooledMySQLConnection':
        """Async context manager entry."""
        pass
    
    async def __aexit__(self, exc_type, exc_val, exc_tb) -> None:
        """Async context manager exit returning connection to pool."""
        pass

async def connect(**kwargs) -> Union[MySQLConnection, PooledMySQLConnection]:
    """
    Create async database connection with optional pooling.
    
    When pool parameters are provided, returns PooledMySQLConnection.
    Otherwise returns MySQLConnection.
    """
    pass

import asyncio
import mysql.connector.aio

async def main():
    # Create async connection
    connection = await mysql.connector.aio.connect(
        host='localhost',
        user='myuser',
        password='mypassword',
        database='mydatabase'
    )
    
    # Create async cursor
    cursor = connection.cursor()
    
    # Execute query asynchronously
    await cursor.execute("SELECT id, name FROM users WHERE age > %s", (25,))
    
    # Fetch results asynchronously
    async for (user_id, name) in cursor:
        print(f"User {user_id}: {name}")
    
    # Cleanup
    await cursor.close()
    await connection.close()

# Run async function
asyncio.run(main())

import asyncio
import mysql.connector.aio

async def main():
    # Automatic async connection cleanup
    async with mysql.connector.aio.connect(
        host='localhost',
        user='myuser', 
        password='mypassword',
        database='mydatabase'
    ) as connection:
        
        # Automatic async cursor cleanup
        async with connection.cursor(dictionary=True) as cursor:
            await cursor.execute("SELECT COUNT(*) as total FROM users")
            result = await cursor.fetchone()
            print(f"Total users: {result['total']}")
            # Cursor automatically closed
        # Connection automatically closed

asyncio.run(main())

import asyncio
import mysql.connector.aio

async def transfer_funds(from_account: int, to_account: int, amount: float):
    async with mysql.connector.aio.connect(
        host='localhost',
        user='myuser',
        password='mypassword',
        database='mydatabase'
    ) as connection:
        
        try:
            # Start transaction
            await connection.start_transaction()
            
            async with connection.cursor() as cursor:
                # Debit from account
                await cursor.execute(
                    "UPDATE accounts SET balance = balance - %s WHERE id = %s",
                    (amount, from_account)
                )
                
                # Credit to account
                await cursor.execute(
                    "UPDATE accounts SET balance = balance + %s WHERE id = %s", 
                    (amount, to_account)
                )
                
                # Check if both operations affected rows
                if cursor.rowcount == 0:
                    raise ValueError("Account not found")
            
            # Commit transaction
            await connection.commit()
            print(f"Transferred {amount} from {from_account} to {to_account}")
            
        except Exception as err:
            # Rollback on error
            await connection.rollback()
            print(f"Transfer failed: {err}")
            raise

asyncio.run(transfer_funds(1, 2, 100.0))

import asyncio
import mysql.connector.aio

async def worker_task(worker_id: int):
    """Async worker using pooled connection."""
    # Get connection from async pool
    async with mysql.connector.aio.connect(
        host='localhost',
        user='myuser',
        password='mypassword',
        database='mydatabase',
        pool_name='async_pool',
        pool_size=5
    ) as connection:
        
        async with connection.cursor() as cursor:
            await cursor.execute("SELECT SLEEP(%s)", (1,))
            await cursor.fetchone()
            
        print(f"Async worker {worker_id} completed")

async def main():
    # Create multiple async tasks
    tasks = [worker_task(i) for i in range(10)]
    
    # Run tasks concurrently
    await asyncio.gather(*tasks)
    print("All async workers completed")

asyncio.run(main())

import asyncio
import mysql.connector.aio

async def process_batch(batch_data: List[Dict]):
    """Process batch of data asynchronously."""
    async with mysql.connector.aio.connect(
        host='localhost',
        user='myuser',
        password='mypassword',
        database='mydatabase'
    ) as connection:
        
        async with connection.cursor() as cursor:
            # Prepare batch insert
            insert_query = "INSERT INTO processed_data (id, value, timestamp) VALUES (%s, %s, NOW())"
            
            # Execute batch asynchronously
            for item in batch_data:
                await cursor.execute(insert_query, (item['id'], item['value']))
            
            await connection.commit()
            print(f"Processed batch of {len(batch_data)} items")

async def main():
    # Sample data batches
    batches = [
        [{'id': 1, 'value': 'A'}, {'id': 2, 'value': 'B'}],
        [{'id': 3, 'value': 'C'}, {'id': 4, 'value': 'D'}],
        [{'id': 5, 'value': 'E'}, {'id': 6, 'value': 'F'}]
    ]
    
    # Process all batches concurrently
    tasks = [process_batch(batch) for batch in batches]
    await asyncio.gather(*tasks)
    print("All batches processed")

asyncio.run(main())

import asyncio
import mysql.connector.aio

async def stream_large_dataset():
    """Stream large dataset asynchronously."""
    async with mysql.connector.aio.connect(
        host='localhost',
        user='myuser',
        password='mypassword',
        database='mydatabase'
    ) as connection:
        
        async with connection.cursor() as cursor:
            await cursor.execute("SELECT * FROM large_table ORDER BY id")
            
            # Stream results asynchronously
            count = 0
            async for row in cursor:
                # Process each row as it arrives
                print(f"Processing row {count}: {row[0]}")
                count += 1
                
                # Yield control to other tasks periodically
                if count % 1000 == 0:
                    await asyncio.sleep(0)  # Yield control
                    
            print(f"Streamed {count} rows")

asyncio.run(stream_large_dataset())

import asyncio
import mysql.connector.aio

async def sync_data_between_databases():
    """Sync data between two databases asynchronously."""
    
    # Connect to source database
    source_conn = await mysql.connector.aio.connect(
        host='source.mysql.example.com',
        user='myuser',
        password='mypassword',
        database='source_db'
    )
    
    # Connect to destination database  
    dest_conn = await mysql.connector.aio.connect(
        host='dest.mysql.example.com',
        user='myuser',
        password='mypassword',
        database='dest_db'
    )
    
    try:
        # Get cursors for both connections
        source_cursor = source_conn.cursor(dictionary=True)
        dest_cursor = dest_conn.cursor()
        
        # Read from source
        await source_cursor.execute("SELECT * FROM users WHERE updated_at > %s", ('2024-01-01',))
        
        # Process and insert to destination
        async for user in source_cursor:
            await dest_cursor.execute(
                "INSERT INTO users (id, name, email) VALUES (%s, %s, %s) ON DUPLICATE KEY UPDATE name=%s, email=%s",
                (user['id'], user['name'], user['email'], user['name'], user['email'])
            )
        
        # Commit destination changes
        await dest_conn.commit()
        print("Data sync completed")
        
    finally:
        # Cleanup both connections
        await source_cursor.close()
        await dest_cursor.close()
        await source_conn.close()
        await dest_conn.close()

asyncio.run(sync_data_between_databases())

import asyncio
import mysql.connector.aio

async def query_with_timeout():
    """Execute query with timeout and error handling."""
    try:
        # Set timeout for entire operation
        async with asyncio.timeout(30):  # 30 second timeout
            async with mysql.connector.aio.connect(
                host='localhost',
                user='myuser',
                password='mypassword',
                database='mydatabase',
                connect_timeout=10  # Connection timeout
            ) as connection:
                
                async with connection.cursor() as cursor:
                    # Long-running query
                    await cursor.execute("SELECT * FROM large_table WHERE complex_condition = %s", ('value',))
                    
                    results = await cursor.fetchall()
                    print(f"Query returned {len(results)} rows")
                    
    except asyncio.TimeoutError:
        print("Query timed out")
    except mysql.connector.Error as err:
        print(f"Database error: {err}")
    except Exception as err:
        print(f"Unexpected error: {err}")

asyncio.run(query_with_timeout())