IndexError string index out of range when referencing first character - python

Here is my code (currently):
conn = sqlite3.connect(db)
conn.text_factory = str #bugger 8-bit bytestrings
cur = conn.cursor()
reader = csv.reader(open(csvfile, "rU"), delimiter = '\t')
for Number, Name, Message, Datetime, Type in reader:
# populate subscriber table
if str(Number)[0] == '1': # errors on this line
tmpNumber = str(Number)[1:]
Number = int(tmpNumber)
cur.execute('INSERT OR IGNORE INTO subscriber (name, phone_number) VALUES (?,?)', (Name, Number))
cur.close()
conn.close()
It returns this error on the line commented to indicate where the error lies:
IndexError: string index out of range
All of the numbers have values, but if the phone number starts with a 1 I want to remove the 1 before inserting it into the database. Why won't this work? I've converted it to a string before trying to reference the first character, so I don't understand why this isn't working.

Seems like you are getting an empty string. Try replacing your if statement with the following and see if it works.
if str(Number).startswith('1'):
(Edited to reflect #kindall 's suggestion of using startswith instead of slicing [:1]).

Related

Python: Incorrect number of bindings supplied when EXECUTEMANY

Trying to pick up some python. I'm quite new to it at the moment.
I created the code below, but it returns an error.
I am able to get it to work when creating a second column and write multiple values to the db but a single value doesn't seem to work. Probably a list, tuple thing, but can not figure out what exactly.
Error:
Traceback (most recent call last):
File "test.py", line 15, in <module>
cursor.executemany("INSERT INTO combination VALUES (?)", combination)
sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 2 supplied.
Code:
import sqlite3
conn = sqlite3.connect("combinations.db")
cursor = conn.cursor()
cursor.execute(r"create table if not exists combination (string text)")
combination = []
chars = "abcd"
for char1 in chars:
for char2 in chars:
combination.append((char1+char2))
cursor.executemany("INSERT INTO combination VALUES (?)", combination)
conn.commit()
You missed making the string into a tuple when adding to the list. The argument to executemany expects a list of iterables, so if you pass it a single string 'ab' in the list, it will treat it as a 2-item iterator of a & b - hence the error.
You need to make the string 'ab' into a 1-item tuple like ('ab',). You do this by adding a trailing comma to the expression you're appending:
combination.append((char1+char2,))
Full code:
import sqlite3
conn = sqlite3.connect("combinations.db")
cursor = conn.cursor()
cursor.execute(r"create table if not exists combination (string text)")
combination = []
chars = "abcd"
for char1 in chars:
for char2 in chars:
combination.append((char1+char2,)) # ('ab',) etc.
cursor.executemany("INSERT INTO combination VALUES (?)", combination)
conn.commit()

How to fix python hardcoded dictionary encoding issue

Error:
pymysql.err.InternalError: (1366, "Incorrect string value: '\\xEF\\xBF\\xBD 20...' for column 'history' at row 1")
I've received a few variations of this as I've tried to tweak my dictionary, always in the history column, the only variations is the characters it tells me are issues.
I can't post the dictionary because it's got sensitive information, but here is the jist:
I started with 200 addresses (including state, zip, etc) that needed
to be validated, normalized and standardized for DB insertion.
I spent a lot of time on google maps validating and standardizing.
I decided to get fancy, and put all the crazy accented letters in the addresses of these world addresses (often copies from google because I don't know how to type and A with an o over it, lol), Singapore to Brazil, everywhere.
I ended up with 120 unique addresses in my dictionary after processing.
Everything works 100% perfectly when INSERTING the data in SQLite and OUTPUTING to a CSV. The issue is exclusively with MySQL and some sneaky un-viewable characters.
Note: I used this to remove the accents after 7 hours of copy/pasting to notepad, encoding it with notepad++ and just trying to processes the data in a way that made it all the correct encoding. I think I did lose the version with the accents and only have this tools output now.
I do not see "\xEF\xBF\xBD 20..." in my dictionary I only see text. Currently I don't even see "20"... those two chars helped me find the previous issues.
Code I can show:
def insert_tables(cursor, assets_final, ips_final):
#Insert Asset data into asset table
field_names_dict = get_asset_field_names(assets_final)
sql_field_names = ",".join(field_names_dict.keys())
for key, row in assets_final.items():
insert_sql = 'INSERT INTO asset(' + sql_field_names + ') VALUES ("' + '","'.join(field_value.replace('"', "'") for field_value in list(row.values())) + '")'
print(insert_sql)
cursor.execute(insert_sql)
#Insert IP data into IP table
field_names_dict = get_ip_field_names(ips_final)
sql_field_names = ",".join(field_names_dict.keys())
for hostname_key, ip_dict in ips_final.items():
for ip_key, ip_row in ip_dict.items():
insert_sql = 'INSERT INTO ip(' + sql_field_names + ') VALUES ("' + '","'.join(field_value.replace('"', "'") for field_value in list(ip_row.values())) + '")'
print(insert_sql)
cursor.execute(insert_sql)
def output_sqlite_db(sqlite_file, assets_final, ips_final):
conn = sqlite3.connect(sqlite_file)
cursor = conn.cursor()
insert_tables(cursor, assets_final, ips_final)
conn.commit()
conn.close()
def output_mysql_db(assets_final, ips_final):
conn = mysql.connect(host=config.mysql_ip, port=config.mysql_port, user=config.mysql_user, password=config.mysql_password, charset="utf8mb4", use_unicode=True)
cursor = conn.cursor()
cursor.execute('USE ' + config.mysql_DB)
insert_tables(cursor, assets_final, ips_final)
conn.commit()
conn.close()
EDIT: Could this have something to do with the fact I'm using Cygwin as my terminal? HA! I added this line and got a different message (now using the accented version again):
cursor.execute('SET NAMES utf8')
Error:
pymysql.err.InternalError: (1366, "Incorrect string value: '\\xC5\\x81A II...' for column 'history' at row 1")
I can shine a bit of light on the messages that you have supplied:
Case 1:
>>> import unicodedata as ucd
>>> s1 = b"\xEF\xBF\xBD"
>>> s1
b'\xef\xbf\xbd'
>>> u1 = s1.decode('utf8')
>>> u1
'\ufffd'
>>> ucd.name(u1)
'REPLACEMENT CHARACTER'
>>>
Looks like you have obtained some bytes encoded in an encoding other than utf8 (e.g. cp1252) then tried bytes.decode(encoding='utf8', errors='strict'). This detected some errors. You then decoded again with errors="replace". This raised no exceptions. However your data has had the error bytes replaced by the replacement character (U+FFFD). Then you encoded your data using str.encodeso that you could write to a file or database. Each replacement characters turns up as 3 hex bytes EF BF BD.
... more to come
Case 2:
>>> s2 = b"\xC5\x81A II"
>>> s2
b'\xc5\x81A II'
>>> u2 = s2.decode('utf8')
>>> u2
'\u0141A II'
>>> ucd.name(u2[0])
'LATIN CAPITAL LETTER L WITH STROKE'
>>>

Trying to insert value from txt file with sqlite in python

def quantity():
i = 0
x = 1
file = open("john.txt", "r")
while i < 5000:
for line in file:
c.execute("INSERT INTO test (playerNAME, playerID) VALUES ("+line+", "+str(x)+")")
conn.commit()
x = random.randint(100,10000000000000000)
i += 1
I try to iterate through the John.txt file and insert each value into a table. The first word in the txt file is "abc123". When I run this code there is an error: sqlite3.OperationalError: no such column: abc123
I can get the code to enter the random numbers into playerID but I can't get the txt file query to work...
You need single quotes around the string.
c.execute("INSERT INTO test (playerNAME, playerID) VALUES ('"+line+"', "+str(x)+")")
Otherwise it tries to interpret it as a sql expression and looks for the named column.
More generally you should use parameters or sanitize the incoming data from the file for safety against sql insertion. Even if you trust this particular file. It's a good habit.
c.execute("INSERT INTO test (playerName, playerID) VALUES (?, ?)", (line, x))
Details are here and here is why it's important.
Formatting sql queries via string concatenation is very bad practice.
Variable bindging should always be used:
c.execute("INSERT INTO test (playerNAME, playerID) VALUES (?, ?)", [line, x])
In your case the line probably contains spaces or any punctuation mark.
The sqlite's error string is misleading, though.

Python: Iterating through MySQL columns

I'm wondering if you can help me. I'm trying to change the value in each column if the text matches a corresponding keyword. This is the loop:
for i in range(0, 20, 1):
cur.execute("UPDATE table SET %s = 1 WHERE text rlike %s") %(column_names[i], search_terms[i])
The MySQL command works fine on its own, but not when I put it in the loop. It's giving an error at the first %s
Does anyone have any insights?
This is the error:
_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 '%s = 1 WHERE text rlike %s' at line 1")
Column names looks like
column_names = ["col1","col2","col3"...]
Search terms look like
search_terms = ["'(^| |.|-)word1[;:,. ?-]'","'(^| |.|-)word2[;:,. ?-]'",...]
The right way to do this is to give values to Python, which will quote things correctly.
adapted from voyager's post:
for i in range(0, 20, 1):
cur.execute("UPDATE table SET {} = 1 WHERE text rlike %s".format(column_names[i]),
(search_terms[i],),
)
In this case it's confusing because the column_name isn't a value, it's part of the table structure, so it's inserted using good old string formatting. The search_term is a value, so is passed to cursor.execute() for correct, safe quoting.
(Don't use string manipulation to add the quotes -- you're exposing yourself to SQL injection.)
Missing quotes and wrong parenthesis placement...
for i in range(0, 20, 1):
cur.execute("UPDATE table SET %s = 1 WHERE text rlike '%s'" %(column_names[i], search_terms[i]))
# ^ ^
# (-----------------------------------------------------------------------------------)
Please note, this is not the right way of doing this, if your string may contain quotes by itself...
What about that instead:
for i in range(0, 20, 1):
cur.execute("UPDATE table SET %s = 1 WHERE text rlike ?" % (column_names[i],),
(search_terms[i],))
This uses the % operator to set the column name, but uses an executes parameter to bind the data, letting the DB driver escape all characters that need so.

PostgreSQL TypeError: not all arguments converted during string formatting

I am executing a query in psycopg2 linked up to a PostgreSQL database. Here is the code in question:
with open('dataFile.txt', 'r') as f:
lines = f.readlines()
newLines = [line[:-1] for line in lines]
curr=conn.cursor()
lineString = ','.join(newLines)
curr.execute("SELECT fields.fieldkey FROM fields LEFT JOIN zone ON zone.fieldkey=fields.fieldkey WHERE zone.zonekey = %s;", (newLines[0]))
rows = curr.fetchall()
There's no issue connecting to the DB, and the type of lines[0] is definitely string, I checked that. Is there something wrong in the syntax of my string formatting?
The error I get, to clarify is this:
TypeError: not all arguments converted during string formatting
There must be a comma after lines[0] to make that a tuple.
curr.execute("""
SELECT fields.fieldkey
FROM fields
LEFT JOIN zone ON zone.fieldkey=fields.fieldkey
WHERE zone.zonekey = %s;
""", (lines[0],))
Since the execute method is expecting a sequence (or a mapping) it iterates over the string you provided surrounded by parenthesis. So it is necessary to explicitly make that a tuple. The same result, with clearer code, can be had using the tuple function:
(tuple(lines[0]))

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