How Can My sqllite3 interaction be fixed? - python

I'm trying to get an admin account to edit a 'rank' (basically access level) for one of the profiles in my data-base. The error is:
Traceback (most recent call last):
File "U:/A-level Computor Science/Y12-13/SQL/sqlite/Databases/ork task/Python for SQL V_2.py", line 154, in <module>
main()
File "U:/A-level Computor Science/Y12-13/SQL/sqlite/Databases/ork task/Python for SQL V_2.py", line 9, in main
start_menu()
File "U:/A-level Computor Science/Y12-13/SQL/sqlite/Databases/ork task/Python for SQL V_2.py", line 22, in start_menu
login()
File "U:/A-level Computor Science/Y12-13/SQL/sqlite/Databases/ork task/Python for SQL V_2.py", line 72, in login
Mek_menu()
File "U:/A-level Computor Science/Y12-13/SQL/sqlite/Databases/ork task/Python for SQL V_2.py", line 108, in Mek_menu
where Uzaname = %s""" % (NewRank, Findaname))
sqlite3.OperationalError: unrecognized token: "0rk_D4T4B453"`
The code that seems to be the problem is:
cursor.execute(""" update 0rk_D4T4B453.Da_Boyz
set Rank = %s
where Uzaname = %s""" % (NewRank, Findaname))
Originally, it was all on one line and it didn't work, and now I've tried it on multiple lines and it still doesn't work. So I checked here to see if anyone could help.
EDIT1: Thanks for the suggestions. None of them have fixed the code, but I've narrowed the problem code to: where Uzaname = %s""" % (NewRank, Findaname))

Unless you use ATTACH, SQLite (a file-level database) does not recognize other databases. Usually server-level databases (Oracle, Postgres, SQL Server, etc.) use the database.schema.table reference. However, in SQLite the very database file you connect to is the main database in scope. But ATTACH allows you to connect to other SQLite databases and then recognizes database.table referencing.
Additionally, for best practices:
In sqlite3 and any other Python DB-APIs, use parameterization for literal values and do not format values to SQL statement.
In general Python, stop using the de-emphasized (not deprecated yet) string modulo operator, %. Use str.format or more recent F-string for string formatting. But neither is needed here.
Altogether, if you connect to the 0rk_D4T4B453 database, simply query without database reference:
conn = sqlite3.connect('/path/to/0rk_D4T4B453.db')
cursor = conn.cursor()
# PREPARED STATEMENT WITH QMARK PLACEHOLDERS
sql = """UPDATE Da_Boyz
SET Rank = ?
WHERE Uzaname = ?"""
# BIND WITH TUPLE OF PARAMS IN SECOND ARG
cursor.execute(sql, (NewRank, Findaname))
conn.commit()
If you do connect to a different database, call ATTACH. Here also, you can alias other database with better naming instead of number leading identifier.
cursor.execute("ATTACH '/path/to/0rk_D4T4B453.db' AS other_db")
sql = """UPDATE other_db.Da_Boyz
SET Rank = ?
WHERE Uzaname = ?"""
cursor.execute(sql, (NewRank, Findaname))
conn.commit()
cur.execute("DETACH other_db")

Related

SQL statement failing to execute in Python CGI

I have an update statement in my database that is not executing. As far as I am aware, it is syntactically correct. I used this app to verify the syntax. The except block is all that is being executed and I do not understand why.
Here is the code:
for res_posts in list_of_response_ids:
temp_str = res_posts[0] # first element of res_posts tuple is string
temp_str += ":" + str(output[0])
try:
sql = "UPDATE POST SET res_post_id = %s WHERE post_id = %d;" % (str(temp_str), int(res_posts[1]))
cursor.execute(sql)
except:
print "uh oh"
I can post more code if this is not enough information.
EDIT: Following Jacob's advice, I used raise and got the following error:
Traceback (most recent call last):
File "post.cgi", line 93, in <module>
cursor.execute(sql)
File "/usr/lib64/python2.6/site-packages/MySQLdb/cursors.py", line 173, in execute
self.errorhandler(self, exc, value)
File "/usr/lib64/python2.6/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler
raise errorclass, errorvalue
ProgrammingError: (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ':37 WHERE post_id = 8' at line 1")
Thank you so much!
Based on your traceback, there is something wrong with the type of entry you are using for the res_post_id or post_id. Currently you are not passing a representation of the res_post_id string, but a literal string. If res_post_id is a string in your DB Schema, I would recommend using %r like so:
sql = "UPDATE POST SET res_post_id = %r WHERE post_id = %d;" % (str(temp_str), int(res_posts[1]))
This will properly quote your res_post_id value for insertion.
So your statement should change from this:
UPDATE POST SET res_post_id = :37 WHERE post_id = 8;
...to this:
UPDATE POST SET res_post_id = ':37' WHERE post_id = 8;

Mysql query using python

I'm using python 3.x and mysql.connector to access a Mysql database. I'm having an issuing with querying the database.
When I run the following query, I get the correct result:
cursor.execute("SELECT idx FROM db WHERE name = 'John Smith'")
When I try and run the following query I get an error:
cursor.execute("SELECT idx FROM db WHERE name = %s",'John Smith')
File "<input>", line 1, in <module>
File "C:\Python34\lib\site-packages\mysql\connector\cursor.py", line 515, in execute
self._handle_result(self._connection.cmd_query(stmt))
File "C:\Python34\lib\site-packages\mysql\connector\connection.py", line 488, in cmd_query
result = self._handle_result(self._send_cmd(ServerCmd.QUERY, query))
File "C:\Python34\lib\site-packages\mysql\connector\connection.py", line 395, in _handle_result
raise errors.get_exception(packet)
mysql.connector.errors.ProgrammingError: 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%s' at line 1
I've tried running the following query instead, but it appears that the query searches for "%s" not the string "John Smith"
cursor.execute("SELECT idx FROM db WHERE name = '%s'",'John Smith')
I'm not sure if the error is due to the fact that I'm using a string with spaces in it or not, but I haven't been able to solve the problem.
q="SELECT idx FROM db WHERE name = %s";
cursor.execute(q,'Xander')
Formatting just needs to be changed a little. You were pretty close.
foo = 'John Smith'
cursor.execute("SELECT idx FROM db WHERE name = %s", (foo,))
Take a gander at the links below for more explanation
Python MySQL Parameterized Queries
https://dev.mysql.com/doc/connector-python/en/connector-python-api-mysqlcursor-execute.html
According to the docs, you would need to write:
cursor.execute("SELECT idx FROM db WHERE name = %s", ('John Smith'))
In other words, the parameter-replacement values must be contained in an iterable.
(But see the answer from theClap who correctly adds a semi-colon to force "tupleness" where required).

How to pass variable for dropping table execution in Python's MySQLdb

With this code I tried to delete a table if it exists. But I need to do it via passing
a variables.
import MySQLdb as mdb
conn = mdb.connect(host='db01.myhost.co.nl,
user='pdbois',
passwd='triplex',
db='myxxx')
cursor = conn.cursor()
# Without passing variables this works OK!
#cursor.execute("""drop table if exists testtable""")
# But this break
table_name = "testtable"
cursor.execute("""drop table if exists %s""",(table_name))
conn.close()
But why the way I do it above breaks by giving this error?
File "test_mysql.py", line 63, in <module>
main()
File "test_mysql.py", line 59, in main
create_table()
File "test_mysql.py", line 25, in create_table
cursor.execute("""drop table if exists %s""",(table_name))
File "build/bdist.linux-x86_64/egg/MySQLdb/cursors.py", line 174, in execute
File "build/bdist.linux-x86_64/egg/MySQLdb/connections.py", line 36, in defaulterrorhandler
_mysql_exceptions.ProgrammingError: (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''testtable'' at line 1")
What's the right way to do it?
Update:
Another problem is to create a table via parameter.
sql = "create table %s(
first_name char(20) not null,
last_name char(20))" % mdb.escape_string(table_name)
cursor.execute(sql)
It gives `SyntaxError: EOL while scanning string literal`.
You cannot parameterize the table name, use string formatting and escape the value manually:
cursor.execute("drop table if exists %s" % mdb.escape_string(table_name))

error to use django cursor to save escaped characters

I have a url which I want to save into the MySQL database using the "cursor" tool offered by django, but I keep getting the "not enough arguments for format string" error because this url contains some escaped characters (non-ascii characters). The testing code is fairly short:
test.py
import os
import runconfig #configuration file
os.environ['DJANGO_SETTINGS_MODULE'] = runconfig.django_settings_module
from django.db import connection,transaction
c = connection.cursor()
url = "http://www.academicjournals.org/ijps/PDF/pdf2011/18mar/G%C3%B3mez-Berb%C3%ADs et al.pdf"
dbquery = "INSERT INTO main_crawl_document SET url="+url
c.execute(dbquery)
transaction.commit_unless_managed()
The full error message is
Traceback (most recent call last):
File "./test.py", line 14, in <module>
c.execute(dbquery)
File "/usr/local/lib/python2.6/site-packages/django/db/backends/util.py", line 38, in execute
sql = self.db.ops.last_executed_query(self.cursor, sql, params)
File "/usr/local/lib/python2.6/site-packages/django/db/backends/__init__.py", line 505, in last_executed_query
return smart_unicode(sql) % u_params
TypeError: not enough arguments for format string
Can anybody help me?
You're opening yourself up for a possible SQL injection. Instead, use c.execute() properly:
url = "http://www.academicjournals.org/ijps/PDF/pdf2011/18mar/G%C3%B3mez-Berb%C3%ADs et al.pdf"
dbquery = "INSERT INTO main_crawl_document SET url=?"
c.execute(dbquery, (url,))
transaction.commit_unless_managed()
The .execute method should accept an iterable of parameters to use for escaping, assuming it's the normal dbapi method (which it should be with Django).

mysqldb interfaceError

I have a very weird problem with mysqldb (mysql module for python).
I have a file with queries for inserting records in tables. If I call the functions from the file, it works just fine; but when trying to call one of the functions from another file it throws me a
_mysql_exception.InterfaceError: (0, '')
I really don't get what I'm doing wrong here..
I call the function from buildDB.py :
import create
create.newFormat("HD", 0,0,0)
The function newFormat(..) is in create.py (imported) :
from Database import Database
db = Database()
def newFormat(name, width=0, height=0, fps=0):
format_query = "INSERT INTO Format (form_name, form_width, form_height, form_fps) VALUES ('"+name+"',"+str(width)+","+str(height)+","+str(fps)+");"
db.execute(format_query)
And the class Database is the following :
import MySQLdb
from MySQLdb.constants import FIELD_TYPE
class Database():
def __init__(self):
server = "localhost"
login = "seq"
password = "seqmanager"
database = "Sequence"
my_conv = { FIELD_TYPE.LONG: int }
self.conn = MySQLdb.connection(host=server, user=login, passwd=password, db=database, conv=my_conv)
# self.cursor = self.conn.cursor()
def close(self):
self.conn.close()
def execute(self, query):
self.conn.query(query)
(I put only relevant code)
Traceback :
Z:\sequenceManager\mysql>python buildDB.py
D:\ProgramFiles\Python26\lib\site-packages\MySQLdb\__init__.py:34: DeprecationWa
rning: the sets module is deprecated
from sets import ImmutableSet
INSERT INTO Format (form_name, form_width, form_height, form_fps) VALUES ('HD',0
,0,0);
Traceback (most recent call last):
File "buildDB.py", line 182, in <module>
create.newFormat("HD")
File "Z:\sequenceManager\mysql\create.py", line 52, in newFormat
db.execute(format_query)
File "Z:\sequenceManager\mysql\Database.py", line 19, in execute
self.conn.query(query)
_mysql_exceptions.InterfaceError: (0, '')
The warning has never been a problem before so I don't think it's related.
I got this error when I was trying to use a closed connection.
Problem resolved.. I was initializing the database twice.. Sorry if you lost your time reading this !
I couldn't get your setup to work. I gives me the same error all the time. However the way you connect to and make queries to the db with the query seems to be "non-standard".
I had better luck with this setup:
conn = MySQLdb.Connection(user="user", passwd="******",
db="somedb", host="localhost")
cur = conn.cursor()
cur.execute("insert into Format values (%s,%s,%s,%s);", ("hd",0,0,0))
This way you can take advantage of the db modules input escaping which is a must to mitigate sql injection attacks.

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