python从数据库中获得数据到numpy

ゝ一纸荒年。 2022-07-13 20:43 251阅读 0赞

使用mysql.connector连接mysql数据库

import
       
        mysql.connector 
       
        from
       
        itertools 
       
        import
       
        chain 
       
        import
       
        sys, os 
       
        import
       
        numpy as np user 
       
        =
       
        
       
        '
       
        root
       
        '
       
        pwd 
       
        =
       
        
       
        '
       
        root
       
        '
       
        host 
       
        =
       
        
       
        '
       
        127.0.0.1
       
        '
       
        db 
       
        =
       
        
       
        '
       
        lending
       
        '
       
        select_sql 
       
        =
       
        
       
        "
       
        SELECT id,age FROM mytable
       
        "
       
        count_sql 
       
        =
       
        
       
        "
       
        SELECT count(*) FROM mytable
       
        "
       
        cnx 
       
        =
       
        mysql.connector.connect(user
       
        =
       
        user, password
       
        =
       
        pwd, host
       
        =
       
        host, database
       
        =
       
        db) cursor 
       
        =
       
        cnx.cursor() 
       
        try
       
        : cursor.execute(count_sql) count 
       
        =
       
        0 
       
        #
       
        显示总数
       
        
       
        
       
        for
       
        row1 
       
        in
       
        cursor: count 
       
        =
       
        row1[0]; 
       
        print
       
        (row1) test 
       
        =
       
        np.arange(count
       
        *
       
        2
       
        ).reshape(count,
       
        2
       
        ) numrows 
       
        =
       
        cursor.execute(select_sql) 
       
        print
       
        (
       
        "
       
        ================================
       
        "
       
        ) index 
       
        =
       
        0; 
       
        for
       
        row 
       
        in
       
        cursor: 
       
        print
       
        (row) test[index,:] 
       
        =
       
        np.fromiter(row, dtype
       
        =
       
        (int,int), count
       
        =
       
        1
       
        ) index 
       
        =
       
        index
       
        +
       
        1
       
        
       
        print
       
        (test) 
       
        except
       
        mysql.connector.Error as err: 
       
        print
       
        (
       
        "
       
        query table 'mytable' failed.
       
        "
       
        ) 
       
        print
       
        (
       
        "
       
        Error: {}
       
        "
       
        .format(err.msg)) sys.exit() cnx.commit() cursor.close() cnx.close()

**Numpy常见数据类型**

[![image][]][image 1]

[image]: /images/20220714/cfcb23b832544a88861dca489275ed01.png
[image 1]: https://img-blog.csdn.net/20161205173029265