Python

Question

我一直将 xml 保存在 python 的 SQLServer 数据库中，如下所示：

import pypyodbc as pyodbc
import urllib
from xml.dom.minidom import Document

doc = Document()
base = doc.createElement('PERSONA')
doc.appendChild(base)
entry = doc.createElement('INFORMACION')
base.appendChild(entry)
nombre = doc.createElement('NOMBRE')
contenidoNombre = doc.createTextNode('Jack')
nombre.appendChild(contenidoNombre)
entry.appendChild(nombre)
apellido = doc.createElement('APELLIDO')
contenidoApellido = doc.createTextNode('Black')
apellido.appendChild(contenidoApellido)
entry.appendChild(apellido)

print doc.toxml()

cnxn = pyodbc.connect(
    'Trusted_Connection=yes;DRIVER={SQL Server};SERVER=localhost;DATABASE=HOLA;UID=sa;PWD=CPTZ@VPN-2011'
)

idPerson = 2

cursor = cnxn.cursor()
cursor.execute("INSERT INTO prueba VALUES (?, ?)", (idPerson, doc.toxml()))
cnxn.commit()
print("XML Guardado");

这是数据库的脚本：

USE [HOLA]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[prueba](
    [id] [int] NOT NULL,
    [xml] [xml] NULL,
 CONSTRAINT [PK_prueba] PRIMARY KEY CLUSTERED 
(
    [id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

GO

现在，我想从 Python 更新 XML 字段，我一直在尝试这个：

import pypyodbc as pyodbc
import urllib
from xml.dom import minidom
from xml.dom.minidom import parse, parseString

# Replace text from nodes of the xml
def replaceText(node, newText):
    if node.firstChild.nodeType != node.TEXT_NODE:
        raise Exception("node does not contain text")
    node.firstChild.replaceWholeText(newText)  

# Connection string
cnxn = pyodbc.connect(
    'Trusted_Connection=yes;DRIVER={SQL Server};SERVER=localhost;DATABASE=TEST;UID=sa;PWD=123456'
)

idPersona = 3
# Load the selected row
cursor = cnxn.cursor()
cursor.execute('SELECT id, xml FROM prueba WHERE id=?', (idPersona,))

for row in cursor.fetchall():
    print row[1]

# Create a xml from the result string
xml = row[1]
dom = parseString(xml)

# Update the nodes in the XML
node = dom.getElementsByTagName('NOMBRE')[0]
replaceText(node, "Modificado")
nombre = node.firstChild.nodeValue

node = dom.getElementsByTagName('APELLIDO')[0]
replaceText(node, "Modificado")
apellido = node.firstChild.nodeValue

# Show the result...
print ("Nombre: " + nombre)
print ("Apellido: " + apellido)

# The problem is here...
cursor = cnxn.cursor()
cursor.execute("UPDATE prueba SET xml=? WHERE id=?", (dom, idPersona))
cnxn.commit()
print 'Actualizacion Realizada con Exito'

当程序运行更新查询时，它给了我下一个错误：

Traceback (most recent call last):
  File "C:\Users\cnavarro\Downloads\test.py", line 44, in <module>
    cursor.execute("UPDATE prueba SET xml=? WHERE id=?", (dom, idPersona))
  File "build\bdist.win32\egg\pypyodbc.py", line 1470, in execute
    self._BindParams(param_types)
  File "build\bdist.win32\egg\pypyodbc.py", line 1275, in _BindParams
    if param_types[col_num][0] == 'u':
TypeError: 'type' object has no attribute '__getitem__'

我做错了什么...？

Answer 1

您忘记在将 XML 对象插入 table 之前将其转换回字符串。

您的插入脚本在传递到数据库之前将 XML 文档转换为字符串，并且您的更新脚本从列中解析 XML，因此转换更新后的内容似乎是一致的XML 也是一个字符串。

因此，修复方法是替换行

cursor.execute("UPDATE prueba SET xml=? WHERE id=?", (dom, idPersona))

和

cursor.execute("UPDATE prueba SET xml=? WHERE id=?", (dom.toxml(), idPersona))

Python - Update XML row in SqlServer (TypeError: 'type' object has no attribute '__getitem__')

Python - Update XML row in SqlServer (TypeError: 'type' object has no attribute '__getitem__')

xml

sql-server

pyodbc

minidom

Python - Update XML row in SqlServer (TypeError: 'type' object has no attribute 'getitem')

Python - Update XML row in SqlServer (TypeError: 'type' object has no attribute 'getitem')