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Can't store a pdf file in a MySql table

I need to store a pdf file in MySql. Whether I use escape_string or not, I always get the same error
b_blob = open(dir + fname_only, "rb")
myblob = b_blob.read() ####<- b'%PDF-1.4\n%\xaa\xab\xac\xad\n4 0 obj\n<<\n/Producer (Apache FOP Version 0.94)\
try:
conn = mysql.connector.connect( usual stuff )
cursor =conn.cursor(buffered=True, dictionary=True)
newblob = conn._cmysql.escape_string(myblob)
query = """INSERT INTO `mytable` (`storing`) VALUES('%s')""" %(newblob)
cursor.execute(query)
except Exception as exc:
Functions.error_handler(exc);
return
b_blob.close()
...MySQL server version for the right syntax to use near '\n%\xaa\xab\xac\xad\n4 0 obj\n<<\n/Producer (Apache FOP Version 0.94)\n/Creation' at line 1

So it looks like your problem is arriving from the quotes at the start of your string. I would consider putting double quotes around the newblob variable. Should look like this.
query = """INSERT INTO `mytable` (`storing`) VALUES("%s")""" %(newblob)

SQLite query difficulty

I have a SQLite db with three relational tables. I'm trying to return the max record from a log table along with related columns from the other tables based on the ID relationships.
I created the query in DB Browser and verified it returns the expected record however, when I use the exact same query statement in my python code it never steps into the 'for' loop.
SQL statement in python -
def GetLastLogEntry():
readings = ()
conn = sqlite3.connect(dbName)
conn.row_factory = sqlite3.Row
cursor = conn.cursor()
cursor.execute("SELECT f.FoodCategory, f.FoodName, gs.FoodWeight,
gsl.GrillDateTime, gsl.CurrentGrillTemp, gsl.TargetGrillTemp,
gsl.CurrentFoodTemp, gsl.TargetFoodTemp, gsl.CurrentOutsideTemp,
gsl.CurrentOutsideHumidity FROM Food as f, GrillSession as gs,
GrillSessionLog as gsl WHERE f.FoodId = gs.FoodId AND
gs.GrillSessionID = gsl.GrillSessionID AND gsl.GrillSessionLogID =
(SELECT MAX(GrillSessionLog.GrillSessionLogID) FROM
GrillSessionLog, GrillSession WHERE GrillSessionLog.GrillSessionID
= GrillSession.GrillSessionID AND GrillSession.ActiveSession =
1)")
for row in cursor:
print("In for loop")
readings = readings + (row['FoodCategory'], row['FoodName'])
print("Food Cat = " + row['FoodCategory'])
cursor.close()
return readings
The query in DB Browser returns only one row which is what I'm trying to have happen in the python code.

Just discovered the issue....
Using DB Browser, I updated a record I'm using for testing but failed to "write" the change to the database table. As a result, every time I was executing my python code against the table it was executing the query with the original record values because my change wasn't yet committed via DB Browser.
Huge brain fart on that one.... Hopefully it will be a lesson learned for someone else in the future.

How to create permanent MS Access Query by Python 3.5.1?

I have about 40 MS Access Databases and have some troubles if need to create or transfer one of MS Access Query (like object) from one db to other dbs.
So I tried to solve this problem with pyodbc but.. as I saw pyodbc doesn't support to create new, permanent MS Access Query (object).
I can connect to db, create or delete tables/rows but can't to create and save new query.
import pyodbc
odbc_driver = r"{Microsoft Access Driver (*.mdb, *.accdb)}"
db_test1 = r'''..\Test #1.accdb'''
db_test2 = r'''..\Test #2.accdb'''
db_test3 = r'''..\Test #3.accdb'''
db_test4 = r'''..\Test #4.accdb'''
db_test_objects = [db_test1, db_test2, db_test3, db_test4]
odbc_conn_str = "Driver=%s;DBQ=%s;" % (odbc_driver, db_file)
print (odbc_conn_str)
conn = pyodbc.connect(odbc_conn_str)
odbc_cursor = conn.cursor()
NewQuery = "CREATE TABLE TestTable(symbol varchar(15), leverage double)"
odbc_cursor.execute(NewQuery)
conn.commit()
conn.close()
SO, How to create and save MS Access Query like objects from python?
I tried to search info in Google, but the answers were related with Run SQL code.
On VBA this code looks like:
Public Sub CreateQueryDefX()
Dim base(1 To 4) As String
base(1) = "..\Test #1.accdb"
base(2) = "..\Test #2.accdb"
base(3) = "..\Test #3.accdb"
base(4) = "..\Test #4.accdb"
For i = LBound(base) To UBound(base)
CurrentBase = base(i)
Set dbo = OpenDatabase(CurrentBase)
With dbo
Set QueryNew = .CreateQueryDef("TestQuery", _
"SELECT * FROM TestTable")
RefreshDatabaseWindow
.Close
End With
Next i
RefreshDatabaseWindow
End Sub
Sorry for my English, it's not my native :)
By the way, I know how to solve this by VBA, but I'm interested in solve this by python.
Thank you.

You can use a CREATE VIEW statement to create a saved Select Query in Access. The pyodbc equivalent to your VBA example would be
crsr = conn.cursor()
sql = """\
CREATE VIEW TestQuery AS
SELECT * FROM TestTable
"""
crsr.execute(sql)
To delete that saved query you could simply execute a DROP VIEW statement.
For more information on DDL in Access see
Data Definition Language

Consider the Python equivalent of the VBA running exactly what VBA uses: a COM interface to the Access Object library. With Python's win32com third-party module, you can call the CreateQueryDef method. Do note: this COM interfacing can be applied in other languages such as PHP and R!
Below uses a try/except/finally block to ensure the Access application process closes regardless of error or success of code (similar to VBA's On Error handling):
import win32com.client
# OPEN ACCESS APP AND DATABASE
dbases = ["..\Test #1.accdb", "..\Test #2.accdb", "..\Test #3.accdb", "..\Test #4.accdb"]
try:
oApp = win32com.client.Dispatch("Access.Application")
# CREATE QUERYDEF
for db in dbases:
oApp.OpenCurrentDatabase(db)
currentdb = oApp.CurrentDb()
currentdb.CreateQueryDef("TestQuery", "SELECT * FROM TestTable")
currentdb = None
oApp.DoCmd.CloseDatabase
except Exception as e:
print(e)
finally:
currentdb = None
oApp.Quit
oApp = None
Also, if you need to run DML statements via pyodbc and not a COM interface, consider distributed queries as Access can query other databases directly in SQL. Below should work in Python (be sure to escape the backslash):
SELECT t.* FROM [C:\Path\To\Other\Database.accdb].TestTable t

using python 2.7 to query sqlite3 database and getting "sqlite3 operational error no such table"

My simple test code is listed below. I created the table already and can query it using the SQLite Manager add-in on Firefox so I know the table and data exist. When I run the query in python (and using the python shell) I get the no such table error
def TroyTest(self, acctno):
conn = sqlite3.connect('TroyData.db')
curs = conn.cursor()
v1 = curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
print v1
conn.close()

When you pass SQLite a non-existing path, it'll happily open a new database for you, instead of telling you that the file did not exist before. When you do that, it'll be empty and you'll instead get a "No such table" error.
You are using a relative path to the database, meaning it'll try to open the database in the current directory, and that is probably not where you think it is..
The remedy is to use an absolute path instead:
conn = sqlite3.connect('/full/path/to/TroyData.db')
You need to loop over the cursor to see results:
curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
for row in curs:
print row[0]
or call fetchone():
print curs.fetchone() # prints whole row tuple

The problem is the SQL statment. you must specify the db name and after the table name...
'''SELECT * FROM db_name.table_name WHERE acctno = ? '''

using pyodbc on ubuntu to insert a image field on SQL Server

I am using Ubuntu 9.04
I have installed the following package versions:
unixodbc and unixodbc-dev: 2.2.11-16build3
tdsodbc: 0.82-4
libsybdb5: 0.82-4
freetds-common and freetds-dev: 0.82-4
python2.6-dev
I have configured /etc/unixodbc.ini like this:
[FreeTDS]
Description = TDS driver (Sybase/MS SQL)
Driver = /usr/lib/odbc/libtdsodbc.so
Setup = /usr/lib/odbc/libtdsS.so
CPTimeout =
CPReuse =
UsageCount = 2
I have configured /etc/freetds/freetds.conf like this:
[global]
tds version = 8.0
client charset = UTF-8
text size = 4294967295
I have grabbed pyodbc revision 31e2fae4adbf1b2af1726e5668a3414cf46b454f from http://github.com/mkleehammer/pyodbc and installed it using "python setup.py install"
I have a windows machine with Microsoft SQL Server 2000 installed on my local network, up and listening on the local ip address 10.32.42.69. I have an empty database created with name "Common". I have the user "sa" with password "secret" with full privileges.
I am using the following python code to setup the connection:
import pyodbc
odbcstring = "SERVER=10.32.42.69;UID=sa;PWD=secret;DATABASE=Common;DRIVER=FreeTDS"
con = pyodbc.connect(odbcstring)
cur = con.cursor()
cur.execute("""
IF EXISTS(SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 'testing')
DROP TABLE testing
""")
cur.execute('''
CREATE TABLE testing (
id INTEGER NOT NULL IDENTITY(1,1),
myimage IMAGE NULL,
PRIMARY KEY (id)
)
''')
con.commit()
Everything WORKS up to this point. I have used SQLServer's Enterprise Manager on the server and the new table is there.
Now I want to insert some data on the table.
cur = con.cursor()
# using web data for exact reproduction of the error by all.
# I'm actually reading a local file in my real code.
url = 'http://www.forestwander.com/wp-content/original/2009_02/west-virginia-mountains.jpg'
data = urllib2.urlopen(url).read()
sql = "INSERT INTO testing (myimage) VALUES (?)"
Now here on my original question, I was having trouble using cur.execute(sql, (data,)) but now I've edited the question, because following Vinay Sajip's answer below (THANKS), I have changed it to:
cur.execute(sql, (pyodbc.Binary(data),))
con.commit()
And insertion is working perfectly. I can confirm the size of the inserted data using the following test code:
cur.execute('SELECT DATALENGTH(myimage) FROM testing WHERE id = 1')
data_inside = cur.fetchone()[0]
assert data_inside == len(data)
Which passes perfectly!!!
Now the problem is on retrieval of the data back.
I am trying the common approach:
cur.execute('SELECT myimage FROM testing WHERE id = 1')
result = cur.fetchone()
returned_data = str(result[0]) # transforming buffer object
print 'Original: %d; Returned: %d' % (len(data), len(returned_data))
assert data == returned_data
However that fails!!
Original: 4744611; Returned: 4096
Traceback (most recent call last):
File "/home/nosklo/devel/teste_mssql_pyodbc_unicode.py", line 53, in <module>
assert data == returned_data
AssertionError
I've put all the code above in a single file here, for easy testing of anyone that wants to help.
Now for the question:
I want python code to insert an image file into mssql. I want to query the image back and show it to the user.
I don't care about the column type in mssql. I am using the "IMAGE" column type on the example, but any binary/blob type would do, as long as I get the binary data for the file I inserted back unspoiled. Vinay Sajip said below that this is the preferred data type for this in SQL SERVER 2000.
The data is now being inserted without errors, however when I retrieve the data, only 4k are returned. (Data is truncated on 4096).
How can I make that work?
EDITS: Vinay Sajip's answer below gave me a hint to use pyodbc.Binary on the field. I have updated the question accordingly. Thanks Vinay Sajip!
Alex Martelli's comment gave me the idea of using the DATALENGTH MS SQL function to test if the data is fully loaded on the column. Thanks Alex Martelli !

Huh, just after offering the bounty, I've found out the solution.
You have to use SET TEXTSIZE 2147483647 on the query, in addition of text size configuration option in /etc/freetds/freetds.conf.
I have used
cur.execute('SET TEXTSIZE 2147483647 SELECT myimage FROM testing WHERE id = 1')
And everything worked fine.
Strange is what FreeTDS documentation says about the text size configuration option:
default value of TEXTSIZE, in bytes. For text and image datatypes, sets the maximum width of any returned column. Cf. set TEXTSIZE in the T-SQL documentation for your server.
The configuration also says that the maximum value (and the default) is 4,294,967,295. However when trying to use that value in the query I get an error, the max number I could use in the query is 2,147,483,647 (half).
From that explanation I thought that only setting this configuration option would be enough. It turns out that I was wrong, setting TEXTSIZE in the query fixed the issue.
Below is the complete working code:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import pyodbc
import urllib2
odbcstring = "SERVER=10.32.42.69;UID=sa;PWD=secret;DATABASE=Common;DRIVER=FreeTDS"
con = pyodbc.connect(odbcstring)
cur = con.cursor()
cur.execute("""
IF EXISTS(SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 'testing')
DROP TABLE testing
""")
cur.execute('''
CREATE TABLE testing (
id INTEGER NOT NULL IDENTITY(1,1),
myimage IMAGE NULL,
PRIMARY KEY (id)
)
''')
con.commit()
cur = con.cursor()
url = 'http://www.forestwander.com/wp-content/original/2009_02/west-virginia-mountains.jpg'
data = urllib2.urlopen(url).read()
sql = "INSERT INTO testing (myimage) VALUES (?)"
cur.execute(sql, (pyodbc.Binary(data),))
con.commit()
cur.execute('SELECT DATALENGTH(myimage) FROM testing WHERE id = 1')
data_inside = cur.fetchone()[0]
assert data_inside == len(data)
cur.execute('SET TEXTSIZE 2147483647 SELECT myimage FROM testing WHERE id = 1')
result = cur.fetchone()
returned_data = str(result[0])
print 'Original: %d; Returned; %d' % (len(data), len(returned_data))
assert data == returned_data

I think you should be using a pyodbc.Binary instance to wrap the data:
cur.execute('INSERT INTO testing (myimage) VALUES (?)', (pyodbc.Binary(data),))
Retrieving should be
cur.execute('SELECT myimage FROM testing')
print "image bytes: %r" % str(cur.fetchall()[0][0])
UPDATE: The problem is in insertion. Change your insertion SQL to the following:
"""DECLARE #txtptr varbinary(16)
INSERT INTO testing (myimage) VALUES ('')
SELECT #txtptr = TEXTPTR(myimage) FROM testing
WRITETEXT testing.myimage #txtptr ?
"""
I've also updated the mistake I made in using the value attribute in the retrieval code.
With this change, I'm able to insert and retrieve a 320K JPEG image into the database (retrieved data is identical to inserted data).
N.B. The image data type is deprecated, and is replaced by varbinary(max) in later versions of SQL Server. The same logic for insertion/retrieval should apply, however, for the newer column type.

I had a similar 4096 truncation issue on TEXT fields, which SET TEXTSIZE 2147483647 fixed for me, but this also fixed it for me:
import os
os.environ['TDSVER'] = '8.0'