I'm playing around with win32com.client for python to try to write/insert a row to a MS Access table. I've found an example of how to connect and query an Access table here. Basically, their code slightly modified for my own use is:
import win32com.client
connection = win32com.client.Dispatch(r'ADODB.Connection')
DSN = 'PROVIDER=Microsoft.Jet.OLEDB.4.0;DATA SOURCE=c:\\testdb.mdb;'
connection.Open(DSN)
recordset = win32com.client.Dispatch(r'ADODB.Recordset')
recordset.Open('SELECT * FROM Table1', connection, 1, 3)
fields_dict = {}
for x in range(recordset.Fields.Count):
fields_dict[x] = recordset.Fields.Item(x).Name
print fields_dict[x], recordset.Fields.Item(x).Value
So this tells me how to execute a select statement on the Access table. I'd like to be able to write rows and data to the table. When using win32com for MS Office products, I tend to dive into the MSDN pages and try to interpret the VBA code for python code, but this one has me a bit handcuffed. Couple that with no examples found on the internet after lengthy searches has made me second guess whether or not this is possible? hopefully someone out there has played with this before and has a suggestion.
As I mentioned in my comment to the question, using pyodbc (or pypyodbc) and the Access ODBC driver is a more common way of doing CRUD operations, but if you really want to use win32com and OLEDB then you could do an UPDATE like this:
import win32com.client
# ADODB constants
adVarWChar = 202
adInteger = 3
adParamInput = 1
connection = win32com.client.Dispatch(r'ADODB.Connection')
DSN = (
r'PROVIDER=Microsoft.Jet.OLEDB.4.0;'
r'DATA SOURCE=C:\Users\Public\mdbTest.mdb;'
)
connection.Open(DSN)
cmd = win32com.client.Dispatch(r'ADODB.Command')
cmd.ActiveConnection = connection
cmd.CommandText = "UPDATE Donors SET LastName = ? WHERE ID = ?"
cmd.Parameters.Append(cmd.CreateParameter("?", adVarWChar, adParamInput, 255))
cmd.Parameters.Append(cmd.CreateParameter("?", adInteger, adParamInput))
cmd.Parameters(0).Value = "Thompson"
cmd.Parameters(1).Value = 10
cmd.Execute()
connection.Close()
Related
My goal is to display SQL queries via the Python console using the Win32com module. I am able to use a comobject to access and successfully display the fields of a SQL query however when i try to display rows i am falling into Exceptions.
Background
I have used PYODBC which works great however there is a limitation based off what SQL providers are installed and whether TLS 1.2 is enforced. The software sometimes is installed to an external SQL server and therefore no provider on the software's server that can always establish a connection. This is why i am now using the kernal of the software via com objects to access the DB as this circumvents the pitfalls of the provider needing to be installed or the latest Windows update to allow TLS 1.2 connections etc.
Win32com Code that works for me using Fields
import win32com.client
import win32com
"""Connection"""
objprox = win32com.client.Dispatch("****.DbObjectProxy") #Blanked out for security of Software
"""Set Query"""
sql1 = "select * from ServiceConsumer_t"
dbq1 = objprox.DoDatabaseQuery(sql1)
dbq1.Open(sql1)
"""Specify & Print result"""
while not dbq1.EOF:
col1 = dbq1.Fields("ID").Value
dbq1.MoveNext()
print(col1)
"""Close Session"""
dbq1.Close()
Output of the above is:
{9CAFD41E-D322-4234-BF80-CF6E11A724A0}
{CE4AAE72-0889-41E8-BDB2-ED96696DDB91}
{DC18008F-2C84-4EB4-BCCB-D94FF96E0564}
{1AAB143C-8393-4C1E-BE94-7AB44788D4E4}
This is correct as I am specifying the ID column to output and using MoveNext() to iterate. This shows I am close to my goal, however, the below code for displaying the rows never appears to work, I am now lost on why?
Win32com Code that does not work for me to display rows:
import win32com.client
import win32com
"""Connection"""
objprox = win32com.client.Dispatch("*****.DbObjectProxy") #Blanked out for security of Software
"""Set Query"""
sql2 = "select * from ServiceConsumer_t"
dbq2 = objprox.DoDatabaseQuery(sql2)
dbq2.Open(sql2)
"""Specify & Print result"""
while not dbq2.EOF:
dbq2.MoveFirst()
res = dbq2.GetRows()
dbq2.MoveNext()
print(res)
"""Close Session"""
dbq2.Close()
From this, I simply get the exception that the object GetRows has no attribute. Looking online there is very little surrounding this. Please can you suggest why the code is not working for displaying all row results? Ideally, I would like the column names displayed too.
Assuming your COM object aligns to the ADODB object, GetRows does the following:
Retrieves multiple records of a Recordset object into an array.
In Python, this array or multidimensional object translates as a nested tuple without metadata like columns names:
rst.MoveFirst()
res = rst.GetRows() # TUPLE OF TUPLES
# LOOP THROUGH ROWS
for i in range(len(res)):
# LOOP THROUGH COLUMNS
for j in range(len(res[i])):
print(res[i][j])
ADODB example:
import win32com.client
# OPEN SQL SERVER DATABASE CONNECTION
conn = win32com.client.gencache.EnsureDispatch("ADODB.Connection")
conn.Open(
"Driver={ODBC Driver 17 for SQL Server};"
f"Server=myServer;Database=myDatabase;"
"Trusted_Connection=Yes;"
)
# OPEN RECORDSET
rst = win32com.client.gencache.EnsureDispatch("ADODB.Recordset")
rst.Open("SELECT * FROM myTable", conn)
rst.MoveFirst()
res = rst.GetRows()
# LOOP THROUGH ROWS
for i in range(len(res)):
# LOOP THROUGH COLUMNS
for j in range(len(res[i])):
print(res[i][j])
# CLOSE AND RELEASE OBJECTS
rst.Close(); conn.Close()
rst = None; conn = None
del rst; del conn
Simple answer to this is I added each column manually to create the full row output like below:
col1 = dbq1.Fields("ID").Value
col2 = dbq1.Fields("Name").Value
col3 = dbq1.Fields("Login").Value
col4 = dbq1.Fields("Email").Value
print(str(col1) + " " + str(col2) + " " str(col3) + " " str(col4))
I'm doing a little python product registration program and the database just doesn't open
I tried to open with sqlite3 library and by suggestion tried with QSqlDatabase, but nothing works. What could this error be? How to solve and connect?
i changed the database connection
path = r'C:\Users\Daniel\Desktop\Sistema NaruHodo\Banco de Dados'
conn = sqlite3.connect(path+r'\produtos.db')
cursor = conn.cursor()
Erro:
C:\Users\Daniel\AppData\Local\Programs\Python\Python37\pythonw.exe "C:/Users/Daniel/Desktop/Sistema NaruHodo/cadastroprodutos.py"
Process finished with exit code -1073740791 (0xC0000409)
Here is the def I'm using to try to get the field data and insert it into the database.
def addProduto(self, produtotext, estoquetext, precocustotext, precovendatext, fornecedorcomboBox):
path = r'C:\Users\Daniel\Desktop\Sistema NaruHodo\Banco de Dados'
conn = sqlite3.connect(path+r'\produtos.db')
produto = str(self.produtotext.text())
estoque = float(self.estoquetext.text())
precocusto = float(self.precocustotext.text())
precovenda = float(self.precovendatext.text())
fornecedor = str(self.fornecedorcomboBox.currentText())
conn.execute(f"""INSERT INTO produ VALUES (null, {produto}, {estoque}, {precocusto}, {precovenda}, {fornecedor})""")
conn.commit()
It looks like you're trying to display the database in a table. I recommend using a QSqlDatabase to create a connection to the database (it does support an SQLite driver). Using this instead of sqlite3 allows for better integration with the PyQt5 framework. Specifically, it can be easily hooked up with a QSqlTableModel and then displayed with a QTableView. For this approach, I suggest you familiarise yourself with model/view programming. It may seem more involved and complex than the QTableWidget you are currently using, but it's well worth it for the easy database integration it offers.
Excuse some of the doc links being for PySide2; the PyQt5 docs aren't exactly complete unfortunately.
I solved the problem, with QSqlDatabase it did not accept and gave drivers error, so I went back to sqlite3. But it was still crashing even connected, so I found that the problem was really in the function that I didn't convert to string
def addProduto(self):
self.banco = sqlite3.connect('Vendas.db')
self.cursor = banco.cursor()
Nome = self.produtotext.text()
Quant = self.estoquetext.text()
Valor = self.precocustotext.text()
Preco = self.precovendatext.text()
Forn = self.fornecedorcomboBox.currentText()
if Nome != '' or Quant != '' or Valor != '' or Preco != '' or Forn != '':
self.banco.execute(f"""INSERT INTO Produtos VALUES ('{Nome}',{Quant}, {Valor}, {Preco}, '{Forn}')""")
self.banco.commit()
self.LoadDatabase()
self.limparcampos()
I am using Sqlalchemy 1.3 to connect to a PostgreSQL 9.6 database (through Psycopg).
I have a very, very raw Sql string formatted using Psycopg2 syntax which I can not modify because of some legacy issues:
statement_str = SELECT * FROM users WHERE user_id=%(user_id)s
Notice the %(user_id)s
I can happily execute that using a sqlalchemy connection just by doing:
connection = sqlalch_engine.connect()
rows = conn.execute(statement_str, user_id=self.user_id)
And it works fine. I get my user and all is nice and good.
Now, for debugging purposes I'd like to get the actual query with the %(user_id)s argument expanded to the actual value. For instance: If user_id = "foo", then get SELECT * FROM users WHERE user_id = 'foo'
I've seen tons of examples using sqlalchemy.text(...) to produce a statement and then get a compiled version. I have that thanks to other answers like this one or this one been able to produce a decent str when I have an SqlAlchemy query.
However, in this particular case, since I'm using a more cursor-specific syntax %(user_id) I can't do that. If I try:
text(statement_str).bindparams(user_id="foo")
I get:
This text() construct doesn't define a bound parameter named 'user_id'
So I guess what I'm looking for would be something like
conn.compile(statement_str, user_id=self.user_id)
But I haven't been able to get that.
Not sure if this what you want but here goes.
Assuming statement_str is actually a string:
import sqlalchemy as sa
statement_str = "SELECT * FROM users WHERE user_id=%(user_id)s"
params = {'user_id': 'foo'}
query_text = sa.text(statement_str % params)
# str(query_text) should print "select * from users where user_id=foo"
Ok I think I got it.
The combination of SqlAlchemy's raw_connection + Psycopg's mogrify seems to be the answer.
conn = sqlalch_engine.raw_connection()
try:
cursor = conn.cursor()
s_str = cursor.mogrify(statement_str, {'user_id': self.user_id})
s_str = s_str.decode("utf-8") # mogrify returns bytes
# Some cleanup for niceness:
s_str = s_str.replace('\n', ' ')
s_str = re.sub(r'\s{2,}', ' ', s_str)
finally:
conn.close()
I hope someone else finds this helpful
I'm trying to do some testing on our JDBC driver using Python.
Initially figuring out JPype, I eventually managed to connect the driver and execute select queries like so (reproducing a generalized snippet):
from __future__ import print_function
from jpype import *
#Start JVM, attach the driver jar
jvmpath = 'path/to/libjvm.so'
classpath = 'path/to/JDBC_Driver.jar'
startJVM(jvmpath, '-ea', '-Djava.class.path=' + classpath)
# Magic line 1
driver = JPackage('sql').Our_Driver
# Initiating a connection via DriverManager()
jdbc_uri = 'jdbc:our_database://localhost:port/database','user', 'passwd')
conn = java.sql.DriverManager.getConnection(jdbc_uri)
# Executing a statement
stmt = conn.createStatement()
rs = stmt.executeQuery ('select top 10 * from some_table')
# Extracting results
while rs.next():
''' Magic #2 - rs.getStuff() only works inside a while loop '''
print (rs.getString('col_name'))
However, I've failed to to batch inserts, which is what I wanted to test. Even when executeBatch() returned a jpype int[], which should indicate a successful insert, the table was not updated.
I then decided to try out py4j.
My plight - I'm having a hard time figuring out how to do the same thing as above. It is said py4j does not start a JVM on its own, and that the Java code needs to be prearranged with a GatewayServer(), so I'm not sure it's even feasible.
On the other hand, there's a library named py4jdbc that does just that.
I tinkered through the dbapi.py code but didn't quite understand the flow, and am pretty much jammed.
If anyone understands how to load a JDBC driver from a .jar file with py4j and can point me in the right direction, I'd be much grateful.
add a commit after adding the records and before retrieving.
conn.commit()
I have met a similar problem in airflow, I used teradata jdbc jars and jaydebeapi to connect teradata database and execute sql:
[root#myhost transfer]# cat test_conn.py
import jaydebeapi
from contextlib import closing
jclassname='com.teradata.jdbc.TeraDriver'
jdbc_driver_loc = '/opt/spark-2.3.1/jars/terajdbc4-16.20.00.06.jar,/opt/spark-2.3.1/jars/tdgssconfig-16.20.00.06.jar'
jdbc_driver_name = 'com.teradata.jdbc.TeraDriver'
host='my_teradata.address'
url='jdbc:teradata://' + host + '/TMODE=TERA'
login="teradata_user_name"
psw="teradata_passwd"
sql = "SELECT COUNT(*) FROM A_TERADATA_TABLE_NAME where month_key='202009'"
conn = jaydebeapi.connect(jclassname=jdbc_driver_name,
url=url,
driver_args=[login, psw],
jars=jdbc_driver_loc.split(","))
with closing(conn) as conn:
with closing(conn.cursor()) as cur:
cur.execute(sql)
print(cur.fetchall())
[root#myhost transfer]# python test_conn.py
[(7734133,)]
[root#myhost transfer]#
In py4j, with your respective JDBC uri:
from py4j.java_gateway import JavaGateway
# Open JVM interface with the JDBC Jar
jdbc_jar_path = '/path/to/jdbc_driver.jar'
gateway = JavaGateway.launch_gateway(classpath=jdbc_jar_path)
# Load the JDBC Jar
jdbc_class = "com.vendor.VendorJDBC"
gateway.jvm.class.forName(jdbc_class)
# Initiate connection
jdbc_uri = "jdbc://vendor:192.168.x.y:zzzz;..."
con = gateway.jvm.DriverManager.getConnection(jdbc_uri)
# Run a query
sql = "select this from that"
stmt = con.createStatement(sql)
rs = stmt.executeQuery()
while rs.next():
rs.getInt(1)
rs.getFloat(2)
.
.
rs.close()
stmt.close()
I am trying to call a SQL Server stored procedure from my Python code, using sqlalchemy. What I'm finding is that no error is raised by the python code and the stored procedure is not executing.
Sample code:
def SaveData(self, aScrapeResult):
sql = "EXECUTE mc.SaveFundamentalDataCSV #pSource='%s',#pCountry='%s',#pOperator='%s',#pFromCountry='%s',#pFromOperator='%s',#pToCountry='%s',#pToOperator='%s',#pSiteName='%s',#pFactor='%s',#pGranularity='%s',#pDescription='%s',#pDataType='%s',#pTechnology = '%s',#pcsvData='%s'"
# Need to convert the data into CSV
util = ListToCsvUtil()
csvValues = util.ListToCsv(aScrapeResult.DataPoints)
formattedSQL = sql % (aScrapeResult.Source ,aScrapeResult.Country,aScrapeResult.Operator ,aScrapeResult.FromCountry ,aScrapeResult.FromOperator ,aScrapeResult.ToCountry ,aScrapeResult.ToOperator ,aScrapeResult.SiteName ,aScrapeResult.Factor ,aScrapeResult.Granularity ,aScrapeResult.Description ,aScrapeResult.DataType ,aScrapeResult.Technology ,csvValues)
DB = create_engine(self.ConnectionString)
DB.connect()
result_proxy = DB.execute(formattedSQL)
results = result_proxy.fetchall()
Examination of formatted SQL yields the following command
EXECUTE mc.SaveFundamentalDataCSV #pSource='PythonTest', #pCountry='UK',
#pOperator='Operator', #pFromCountry='None', #pFromOperator='None',
#pToCountry='None', #pToOperator='None', #pSiteName='None', #pFactor='Factor',
#pGranularity='Hourly', #pDescription='Testing from python',
#pDataType='Forecast',#pTechnology = 'Electricity',
#pcsvData='01-Jan-2012 00:00:00,01-Feb-2012 00:15:00,1,01-Jan-2012 00:00:00,01-Feb-2012 00:30:00,2';
The various versions and software in use is as follows:
SQL Server 2008 R2
Python 2.6.6
SQLAlchemy 0.6.7
I have tested my stored procedure by calling it directly in SQL Server Management Studio with the same parameters with no problem.
It's worth stating that this point that the Python version and the SQL server version are non-changeable. I have no strong allegiance to sqlalchemy and am open to other suggestions.
Any advice would be greatly appreciated, more information can be provided if needed.
Fixed now but open to opinion if I'm using best practice here. I've used the 'text' object exposed by sqlalchemy, working code below:
def SaveData(self, aScrapeResult):
sql = "EXECUTE mc.SaveFundamentalDataCSV #pSource='%s',#pCountry='%s',#pOperator='%s',#pFromCountry='%s',#pFromOperator='%s',#pToCountry='%s',#pToOperator='%s',#pSiteName='%s',#pFactor='%s',#pGranularity='%s',#pDescription='%s',#pDataType='%s',#pTechnology = '%s',#pcsvData='%s'"
# Need to convert the data into CSV
util = ListToCsvUtil()
csvValues = util.ListToCsv(aScrapeResult.DataPoints)
formattedSQL = sql % (aScrapeResult.Source ,aScrapeResult.Country,aScrapeResult.Operator ,aScrapeResult.FromCountry ,aScrapeResult.FromOperator ,aScrapeResult.ToCountry ,aScrapeResult.ToOperator ,aScrapeResult.SiteName ,aScrapeResult.Factor ,aScrapeResult.Granularity ,aScrapeResult.Description ,aScrapeResult.DataType ,aScrapeResult.Technology ,csvValues)
DB = create_engine(self.ConnectionString)
conn = DB.connect()
t = text(formattedSQL).execution_options(autocommit=True)
DB.execute(t)
conn.close()
Hope this proves helpful to someone else!