Develop Reference

Check if a certain number exists in a database using python and add 1 to a variable

I am trying to check if a certain number exists in a database using python.
When it detects the number I am looking for, then I want it to do variable += 1. I do not have any specific code, but here is some example code of what I want it to do.
import pyodbc
one = 0
conn = pyodbc.connect(r'DSN=MACCD')
cursor = conn.cursor()
cursor.execute('SELECT first,second,third,fourth,fifth FROM ExampDatabase')
if "1 is detected in the database":
one += 1
print(one)

Reading the pyodbc docs, you could try this:
import pyodbc
conn = pyodbc.connect(...)
cursor = conn.cursor()
cursor.execute(...)
# whatever number you are looking for
my_target = ...
target_counter = 0
row_counter = 0
while True:
row = cursor.fetchone()
if row is None:
break
row_counter += 1
print(row_counter, row)
if my_target in row:
target_counter += 1
print('rows returned:', row_counter)
print('targets found:', target_counter)

Python code not creating tables on the database but able to query the results postgres

My usecase is to write create a temp table in the postgres database and fetch records from it and insert into a different table.
The code i used is:
import psycopg2
import sys
import pprint
from __future__ import print_function
from os.path import join,dirname,abspath
import xlrd
import os.path
newlist = []
itemidlist = []
def main():
conn_string = "host='prod-dump.cvv9i14mrv4k.us-east-1.rds.amazonaws.com' dbname='ebdb' user='ebroot' password='*********'"
# print the connection string we will use to connect
# print "Connecting to database" % (conn_string)
# get a connection, if a connect cannot be made an exception will be raised here
conn = psycopg2.connect(conn_string)
# conn.cursor will return a cursor object, you can use this cursor to perform queries
cursor = conn.cursor()
dealer_id = input("Please enter dealer_id: ")
group_id = input("Please enter group_id: ")
scriptpath = os.path.dirname('__file__')
filename = os.path.join(scriptpath, 'Winco - Gusti.xlsx')
xl_workbook = xlrd.open_workbook(filename, "rb")
xl_sheet = xl_workbook.sheet_by_index(0)
print('Sheet Name: %s' % xl_sheet.name)
row=xl_sheet.row(0)
from xlrd.sheet import ctype_text
print('(Column #) type:value')
for idx, cell_obj in enumerate(row):
cell_type_str = ctype_text.get(cell_obj.ctype, 'unknown type')
#print('(%s) %s %s' % (idx, cell_type_str, cell_obj.value))
num_cols = xl_sheet.ncols
for row_idx in range(0, xl_sheet.nrows): # Iterate through rows
num_cols = xl_sheet.ncols
id_obj = xl_sheet.cell(row_idx, 1) # Get cell object by row, col
itemid = id_obj.value
#if itemid not in itemidlist:
itemidlist.append(itemid)
# execute our Query
'''
cursor.execute("""
if not exists(SELECT 1 FROM model_enable AS c WHERE c.name = %s);
BEGIN;
INSERT INTO model_enable (name) VALUES (%s)
END;
""" %(itemid,itemid))
'''
cursor.execute("drop table temp_mbp1")
try:
cursor.execute("SELECT p.model_no, pc.id as PCid, g.id AS GROUPid into public.temp_mbp1 FROM products p, \
model_enable me, products_clients pc, groups g WHERE p.model_no = me.name \
and p.id = pc.product_id and pc.client_id = %s and pc.client_id = g.client_id and g.id = %s"\
% (dealer_id,group_id)
except (Exception, psycopg2.DatabaseError) as error:
print(error)
cursor.execute("select count(*) from public.temp_mbp1")
# retrieve the records from the database
records = cursor.fetchall()
# print out the records using pretty print
# note that the NAMES of the columns are not shown, instead just indexes.
# for most people this isn't very useful so we'll show you how to return
# columns as a dictionary (hash) in the next example.
pprint.pprint(records)
if __name__ == "__main__":
main()
The try except block in between the program is not throwing any error but the table is not getting created in the postgres database as i see in the data admin.
The output shown is:
Please enter dealer_id: 90
Please enter group_id: 13
Sheet Name: Winco Full 8_15_17
(Column #) type:value
[(3263,)]
Thanks,
Santosh

You didn't commit the changes, so they aren't saved in the database. Add to the bottom, just below the pprint statement:
conn.commit()

Python: Print only one value of an SQL query result set

from sqlalchemy import create_engine
engine = create_engine('mssql+pymssql://myusername:mypassword#127.0.0.1:1433/AQOA_Core')
connection = engine.connect()
result = connection.execute("""SELECT DISTINCT Distributor FROM Product""")
for row in result:
print row[0]
connection.close()
The above code returns a result set as:
FRANCETV
GAUMONT
M6SND
PATHE
STUDIOCANAL
TF1
WARNER
What if I want to print just one value without changing the query?
Tried print row[0][1], print row[0:1] This was tried to print just the first value FRANCETV
Basically I want to be able to print each one of the values in the result set seperately without making changes to the query.

You can try to access the data by:
connection = engine.connect()
result = connection.execute("""SELECT DISTINCT Distributor FROM Product""")
result_list = result.fetchall()
result_list[0][0]
connection.close()

If you take a look at the pymssql docs, you'll see the cursor object has a fetchone() method.
with engine.connect() as connection:
cursor = connection.cursor()
cursor.execute("""SELECT DISTINCT Distributor FROM Product""")
first_row = cursor.fetchone()
print first_row

file = open("testfile.txt", "w", encoding='utf-8')
mycursor.execute('SELECT * from COMPANY')
myresult = mycursor.fetchall()
counter = 0
y = 0
for x in myresult:
y = 0
while y < 3:
print(y)
file.write("%s\n" % myresult[counter][y])
y = y + 1
counter = counter + 1
file.close()
This is what I concluded from the answers above

Python cursor is returning number of rows instead of rows

Writing a script to clean up some data. Super unoptimized but this cursor is
returning the number of results in the like query rather than the rows what am I doing wrong.
#!/usr/bin/python
import re
import MySQLdb
import collections
db = MySQLdb.connect(host="localhost", # your host, usually localhost
user="admin", # your username
passwd="", # your password
db="test") # name of the data base
# you must create a Cursor object. It will let
# you execute all the query you need
cur = db.cursor()
# Use all the SQL you like
cur.execute("SELECT * FROM vendor")
seen = []
# print all the first cell of all the rows
for row in cur.fetchall() :
for word in row[1].split(' '):
seen.append(word)
_digits = re.compile('\d')
def contains_digits(d):
return bool(_digits.search(d))
count_word = collections.Counter(seen)
found_multi = [i for i in count_word if count_word[i] > 1 and not contains_digits(i) and len(i) > 1]
unique_multiples = list(found_multi)
groups = dict()
for word in unique_multiples:
like_str = '%' + word + '%'
res = cur.execute("""SELECT * FROM vendor where name like %s""", like_str)

You are storing the result of cur.execute(), which is the number of rows. You are never actually fetching any of the results.
Use .fetchall() to get all result rows or iterate over the cursor after executing:
for word in unique_multiples:
like_str = '%' + word + '%'
cur.execute("""SELECT * FROM vendor where name like %s""", like_str)
for row in cur:
print row

Python: tuple indices must be integers, not str when selecting from mysql table

I have following method that I select all the ids from table and append them to a list and return that list. But when execute this code I end up getting tuple indicies must be integers... error. I have attached the error and the print out along with my method:
def questionIds(con):
print 'getting all the question ids'
cur = con.cursor()
qIds = []
getQuestionId = "SELECT question_id from questions_new"
try:
cur.execute(getQuestionId)
for row in cur.fetchall():
print 'printing row'
print row
qIds.append(str(row['question_id']))
except Exception, e:
traceback.print_exc()
return qIds
Printing what my method does:
Database version : 5.5.10
getting all the question ids
printing row
(u'20090225230048AAnhStI',)
Traceback (most recent call last):
File "YahooAnswerScraper.py", line 76, in questionIds
qIds.append(str(row['question_id'][0]))
TypeError: tuple indices must be integers, not str

The python standard mysql library returns tuples from cursor.execute. To get at the question_id field you'd use row[0], not row['question_id']. The fields come out in the same order that they appear in the select statement.
A decent way to extract multiple fields is something like
for row in cursor.execute("select question_id, foo, bar from questions"):
question_id, foo, bar = row

There are multiple cursor types in the MySQLdb module. The default cursor returns the data in a tuple of tuples. When we use a dictionary cursor, the data is sent in a form of Python dictionaries. This way we can refer to the data by their column names. Source
#!/usr/bin/python
# -*- coding: utf-8 -*-
import MySQLdb as mdb
con = mdb.connect('localhost', 'testuser', 'test623', 'testdb')
with con:
cur = con.cursor(mdb.cursors.DictCursor)
cur.execute("SELECT * FROM Writers LIMIT 4")
rows = cur.fetchall()
for row in rows:
print row["Id"], row["Name"]

I know the question is old, but I found another way to do it that I think it is better than the accepted solution. So I'll just leave it here in case anyone needs it.
When creating the cursor you can use
cur = connection.cursor(dictionary=True);
which will allow you to do exactly what you want without any additional modifications.
rows = cur.fetchall()
for row in rows:
print "%s %s %s" % (row["Id"], row["Name"], row["Price"])

you can see here: enter link description here ,I think its your want
#!/usr/bin/python
# -*- coding: utf-8 -*-
import sqlite3 as lite
con = lite.connect('test.db')
with con:
con.row_factory = lite.Row # its key
cur = con.cursor()
cur.execute("SELECT * FROM Cars")
rows = cur.fetchall()
for row in rows:
print "%s %s %s" % (row["Id"], row["Name"], row["Price"])

To retrieve data from database use dictionary cursor
import psycopg2
import psycopg2.extras
con = psycopg2.connect(database="test", user="test", password="test", host="localhost", port="5432")
if con != None:
print "Connection Established..!\n"
else:
print "Database Connection Failed..!\n"
cur = con.cursor(cursor_factory=psycopg2.extras.DictCursor)
cur.execute("SELECT * FROM emp")
rows = cur.fetchall()
for row in rows:
print "%s %s %s" % (row["id"],row["name"],row["address"])
print "\nRecords Display Successfully"
con.commit()
con.close()

Integer indices are not allowed. To get it working you can declare the DICT as specified below:
VarName = {}
Hope this works for you.

row is a tuple. When you do row['question_id'], you are trying to access a tuple using a string index which gives you an error.