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psycopg2 dictionary dump to json

Sorry if this is a noob question, but I am trying to dump a psycopg2 dictionary directly into a json string. I do get a return value in the browser, but it isn't formatted like most of the other json examples I see. The idea being to dump the result of a select statement into a json string and unbundle it on the other end to add into a database on the client side. The code is below and a sample of the return. Is there a better way to do this operation with json and psycopg2?
# initializing variables
location_connection = location_cursor = 0
sql_string = coordinate_return = data = ""
# opening connection and setting cursor
location_connection = psycopg2.connect("dbname='' user='' password=''")
location_cursor = location_connection.cursor(cursor_factory=psycopg2.extras.RealDictCursor)
# setting sql string and executing query
sql_string = "select * from " + tablename + " where left(alphacoordinate," + str(len(coordinate)) + ") = '" + coordinate + "' order by alphacoordinate;"
location_cursor.execute(sql_string)
data = json.dumps(location_cursor.fetchall())
# closing database connection
location_connection.close()
# returning coordinate string
return data
sample return
"[{\"alphacoordinate\": \"nmaan-001-01\", \"xcoordinate\":
3072951151886, \"planetarydiameter\": 288499, \"planetarymass\":
2.020936938e+27, \"planetarydescription\": \"PCCGQAAA\", \"planetarydescriptionsecondary\": 0, \"moons\": 1"\"}]"

You could create the JSON string directly in Postgres using row_to_json:
# setting sql string and executing query
sql_string = "select row_to_json(" + tablename + ") from " + tablename + " where left(alphacoordinate," + str(len(coordinate)) + ") = '" + coordinate + "' order by alphacoordinate;"
location_cursor.execute(sql_string)
data = location_cursor.fetchall()

Why Sqlite3 table wont UPDATE

I've tried making an update to my sqlite3 table but it doesn't seem to work.
marks = "My long name here"
conn = sqlite3.connect('mydb.db')
cur=conn.cursor()
cur.execute("UPDATE '" + str(marks) +"' SET (ENG,KIS,MAT,BIO) = (-1,-1,-1,-1) WHERE (ENG,KIS,MAT,BIO) =('nan','nan','nan','nan')")
conn.commit()
conn.close()
I can't see nay error in my code.

You don't need 4 separate statements.
You can do it in 1 statement with CASE expressions:
UPDATE tablename
SET ENG = CASE WHEN ENG = 'nan' THEN -1 ELSE ENG END,
KIS = CASE WHEN KIS = 'nan' THEN -1 ELSE KIS END,
MAT = CASE WHEN MAT = 'nan' THEN -1 ELSE MAT END,
BIO = CASE WHEN BIO = 'nan' THEN -1 ELSE BIO END
WHERE 'nan' IN (ENG,KIS,MAT,BIO)

This worked, separating them.
marks = "My long name here"
conn = sqlite3.connect('mydb.db')
cur=conn.cursor()
cur.execute("UPDATE '" + str(marks) + "' SET ENG=-1 WHERE ENG='nan'")
cur.execute("UPDATE '" + str(marks) + "' SET KIS=-1 WHERE KIS='nan'")
cur.execute("UPDATE '" + str(marks) + "' SET MAT=-1 WHERE MAT='nan'")
cur.execute("UPDATE '" + str(marks) + "' SET BIO=-1 WHERE BIO='nan'")
conn.commit()
conn.close()
Rather than this.
marks = "My long name here"
conn = sqlite3.connect('mydb.db')
cur=conn.cursor()
cur.execute("UPDATE '" + str(marks) +"' SET (ENG,KIS,MAT,BIO) = (-1,-1,-1,-1) WHERE (ENG,KIS,MAT,BIO) =('nan','nan','nan','nan')")
conn.commit()
conn.close()

Why Does Empty MySQL Database Claim to Have Duplicates (Python 3)?

So I have a quick function that's supposed to upload data (stored in a Python dictionary) to a MySQL database.
def uploadData(of_item):
global DB_HOST
global DB_USER
global DB_PASSWORD
global DB_DATABASE
my_db = connector.connect(host=DB_HOST, user=DB_USER, passwd=DB_PASSWORD, database=DB_DATABASE, port=3306)
my_db.autocommit = True
my_cursor = my_db.cursor()
print("\rThe DB pipeline is now connected.")
slots_text = ", ".join([a[0] for a in of_item.items()])
values_text = ", ".join(["'" + a[1].replace("'", "\\'") + "'" for a in of_item.items()])
set_portion_text = ", ".join([a[0] + " = " + "'" + a[1].replace("'", "\\'") + "'" for a in of_item.items()])
sql = 'INSERT INTO UsersData ({0}) VALUES ({1})'.format(slots_text, values_text)
try:
my_cursor.execute(sql)
row_cnt = my_cursor.rowcount
my_db.commit()
my_cursor.close()
my_db.close()
print("\r" + str(row_cnt) + " is now in UsersData.")
return [True, str(row_cnt)]
except Exception as exception:
print("\n".join(["The update failed for profileID: " + of_item['UniqueId'],
str(exception),
str(sql),
"*",
'Item:',
str(of_item),
"*"]))
my_cursor.close()
my_db.close()
return [False, 0]
Currently, the row_cnt sits at -1, so it should be entirely empty. However, when I execute the function, I'm constantly getting this thrown error:
1062 (23000): Duplicate entry 'ABCDEFGHIJKLMNOPQRSTUVWXYZ-123' for key 'profileId_2'
Now, profileId_2 is just this:
...
UNIQUE KEY `profileId_2` (`profileId`,`companyId`),
...
profileId is whatever the user's unique ID is, and companyId is just a preset (in this case, 123). It's odd that there would be a claimed duplicate, since there's nothing in the database yet.
First, what might be causing this error? Second, how can I get through it and successfully append new entries to UsersData?

Select Column from Table in Django Not Working

I am trying to access the two specific column from the table in Django it is not Working but When I am trying to access select * it is working
I am using postgresql
When I am trying to access select all its working this is I am trying to access for particular column
def bigdataDatabase(X):
engine = sqlalchemy.create_engine('postgresql+psycopg2://postgres:password#localhost/db_name')
con = engine.connect()
result = con.execute(
"Select Orign,Departure From 'table_name' WHERE index = '" + str(X) + "'")
This is not working
I have also tried with this
result = con.execute("Select tablename.Orign,tablename.departure From 'table_name' WHERE index = '" + str(X) + "'")
both the above code is not working
Programming Error column does not exist
But When I am executing all this it is working
result = con.execute("Select * From 'table_name' WHERE index = '" + str(X) + "'")

I have found the solution of the problem the query should be executed like this
result = con.execute('Select "Orign","Departure" From "Table_name" WHERE index = ' + str(X))

python 3.5 selecting and using results from postgres database

I need to write a program which can,firstly, for ip adresses of people who saw my campaign on google, and then give me detailed information about each of these persons.
I have all information in postgres database and use python 3.5
Here is my code:
def get_connection(cursor_factory=None):
conn_string_pg = "host= '" + host + "' dbname = '" + dbname + "' user = '" + user + \
"' password = '" + password + "'"
if cursor_factory is None:
conn_pg = psycopg2.connect(conn_string_pg)
else:
conn_pg = psycopg2.connect(conn_string_pg,
cursor_factory=cursor_factory)
return conn_pg
def find_logs():
select = """ select ip_address from log_files o where o.url like
'%my_campaign'
"""
conn = get_connection(cursor_factory = RealDictCursor)
cur = conn.cursor()
cur.execute(select)
records = cur.fetchone()
for item in records:
select_2 = "select * from log_files where ip_address = %(item)s "
cur.execute(select_2)
logs = cur.fetchone()
return logs
print(find_logs())
cur.close()
Unfortunately I get this error:
psycopg2.ProgrammingError: syntax error at or near "%" LINE 1:
...elect * from web_logs.log_data where ip_address = %(item)s o...

Your string interpolation is incorrect. You're trying to insert the value of item into your select_2 statement, but you don't actually do the string interpolation, so you pass psycopg2 an invalid SQL statement. You want to do something like
select_2 = "select * from log_files where ip_address = {}".format(item)

It's because ip_address = %(item)s it's not a valid sql syntax. You should make string formatting before:
select_2 = "select * from log_files where ip_address = %(item)s " % {'item': item}
And the better way to do it is to give all the transformation to the postgres driver
select_2 = "select * from log_files where ip_address = %s "
cur.execute(select_2, (item, ))