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  • MySQL Python教程(4)

    Class cursor.MySQLCursorBuffered

    该类从Class cursor.MySQLCursorBuffered继承,如果需要,可以在执行完SQL语句后自动缓冲结果集合。
    import mysql.connector
    cnx = mysql.connector.connect()
    # Only this particular cursor will buffer results
    cnx.cursor(buffered=True)
    # All cursors will be buffering by default
    cnx2 = mysql.connector.connect(buffered=True)

    Class cursor.MySQLCursorPrepared
    该类继承cursor.MySQLCursor,使用二进制协议执行prepare statement
    使用方法:
    import mysql.connector
    from mysql.connector.cursor import MySQLCursorPrepared
    cnx = mysql.connector.connect(database='employees')
    cursor = cnx.cursor(cursor_class=MySQLCursorPrepared)
    此时cursor为MySQLCursorPrepared对象。

    举例:
    cursor = cnx.cursor(cursor_class=MySQLCursorPrepared)
    stmt = "SELECT fullname FROM employees WHERE id = ?" # (1)
    cursor.execute(stmt, (5,)) # (2)
    # ... fetch data ...
    cursor.execute(stmt, (10,)) # (3)
    # ... fetch data ...


    Class constants.ClientFlag
    This class provides constants defining MySQL client flags that can be used when the connection is established to configure the session.

    >>> import mysql.connector
    >>> mysql.connector.ClientFlag.FOUND_ROWS
    2

    Class constants.FieldType
    该类不能被实例化,支持所有MySQL的数据类型。
    from __future__ import print_function
    import mysql.connector
    from mysql.connector import FieldType
    cnx = mysql.connector.connect(user='scott', database='test')
    cursor = cnx.cursor()
    cursor.execute(
    "SELECT DATE(NOW()) AS `c1`, TIME(NOW()) AS `c2`, "
    "NOW() AS `c3`, 'a string' AS `c4`, 42 AS `c5`")
    rows = cursor.fetchall()
    for desc in cursor.description:
    colname = desc[0]
    coltype = desc[1]
    print("Column {} has type {}".format(
    colname, FieldType.get_info(coltype)))
    cursor.close()
    cnx.close()

    Class constants.SQLMode
    提供所有已知的SQL服务器模式。具体参见
    http://dev.mysql.com/doc/refman/5.6/en/server-sql-mode.html


    Class constants.CharacterSet
    提供MYSQL的字符集和默认的collations。参见Method MySQLConnection.set_charset_collation

    Class constants.RefreshOption
    该类提供多种flush的操作。
    RefreshOption.GRANT
    Refresh the grant tables, like FLUSH PRIVILEGES.

    RefreshOption.LOG
    Flush the logs, like FLUSH LOGS.

    RefreshOption.TABLES
    Flush the table cache, like FLUSH TABLES.

    RefreshOption.HOSTS
    Flush the host cache, like FLUSH HOSTS.

    RefreshOption.STATUS
    Reset status variables, like FLUSH STATUS.

    RefreshOption.THREADS
    Flush the thread cache.

    RefreshOption.SLAVE
    On a slave replication server, reset the master server information and restart the slave, like RESET SLAVE.

    RefreshOption.MASTER

    On a master replication server, remove the binary log files listed in the binary log index and truncate the index file, like RESET MASTER.

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  • 原文地址:https://www.cnblogs.com/bigbigtree/p/3248126.html
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