Insert a row into a MySQL table when one of the elements is a Python dictionary

Question

I am having trouble inserting an element into a MySQL database.

Here is the code I have:

#!/usr/bin/python
# -*- coding: utf-8 -*-

myData = [ { u'my_text' : {u'id': u'1', u'description' : u'described' }, u'my_id' : u'1' } ]

import MySQLdb as mdb
con = None
con = mdb.connect('localhost', 'abc', 'def', 'ghi');
cur = con.cursor()
con.set_character_set('utf8')
cur.execute('SET NAMES utf8;')
cur.execute('SET CHARACTER SET utf8;')
cur.execute('SET character_set_connection=utf8;')

sql = "INSERT IGNORE INTO MyTable ( 'my_id', 'my_text' ) VALUES ( %(my_id)s, %(my_text)s );"
cur.executemany(sql, myData)
con.commit()

if con: con.close()

My database is created with this:

CREATE TABLE MyTable(
    'my_id' INT(10) unsigned NOT NULL,
    'my_text' TEXT
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

As you can see from the python script one element of my list is a dictionary and it seems to be this that is stopping the insertion into the MySQL database but as I have only started using MySQL in the last few days I may be wrong.

If I make my_text within myData a simple text phrase such as the following everything works fine and the insertion into the database table works fine:

myData = [ { u'my_text' : u'something simple', u'my_id' : u'1' } ]

I want to be able to use this:

myData = [ { u'my_text' : {u'id': u'1', u'description' : u'described' }, u'my_id' : u'1' } ]

What am I doing wrong?

Answer 1

You have at least two choices.

1. Change your table schema:

    CREATE TABLE MyTable( 'my_id' INT(10) unsigned NOT NULL, 'id' INT(10), 'description' TEXT ) ENGINE=MyISAM DEFAULT CHARSET=utf8 sql = "INSERT IGNORE INTO MyTable ( 'my_id', 'id', 'description' ) VALUES ( %s, %s, %s )" myArg = [(dct['my_id'], dct['my_text']['id'], dct['my_text']['description']) for dct in myData] cur.executemany(sql, myArg) 

2. or change the arg passed to cur.executemany :

    myData = [ { u'my_text' : {u'id': u'1', u'description' : u'described' }, u'my_id' : u'1' } ] myArg = [ {'my_txt' : str(dct['my_text']), 'my_id' : dct['my_id']} for dct in myData ] cur.executemany(sql, myArg) 

The advantage of changing the table schema is that you can now select based on id , so the data is richer.

But if you have no need to separate the id from the description, then the second way will work without having to change the table schema.