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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()

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))

Get MSSQL table column names using pyodbc in python

I am trying to get the mssql table column names using pyodbc, and getting an error saying
ProgrammingError: No results. Previous SQL was not a query.
Here is my code:
class get_Fields:
def GET(self,r):
web.header('Access-Control-Allow-Origin', '*')
web.header('Access-Control-Allow-Credentials', 'true')
fields = []
datasetname = web.input().datasetName
tablename = web.input().tableName
cnxn = pyodbc.connect(connection_string)
cursor = cnxn.cursor()
query = "USE" + "[" +datasetname+ "]" + "SELECT COLUMN_NAME,* FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = " + "'"+ tablename + "'"
cursor.execute(query)
DF = DataFrame(cursor.fetchall())
columns = [column[0] for column in cursor.description]
return json.dumps(columns)
how to solve this?

You can avoid this by using some of pyodbc's built in methods. For example, instead of:
query = "USE" + "[" +datasetname+ "]" + "SELECT COLUMN_NAME,* FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = " + "'"+ tablename + "'"
cursor.execute(query)
DF = DataFrame(cursor.fetchall())
Try:
column_data = cursor.columns(table=tablename, catalog=datasetname, schema='dbo').fetchall()
print(column_data)
That will return the column names (and other column metadata). I believe the column name is the fourth element per row. This also relieves the very valid concerns about SQL injection. You can then figure out how to build your DataFrame from the resulting data.
Good luck!

Your line
query = "USE" + "[" +datasetname+ "]" + "SELECT COLUMN_NAME,*...
Will produce something like
USE[databasename]SELECT ...
In SSMS this would work, but I'd suggest to look on proper spacing and to separate the USE-statement with a semicolon:
query = "USE " + "[" +datasetname+ "]; " + "SELECT COLUMN_NAME,*...

Set the database context using the Database attribute when building the connection string
Use parameters any time you are passing user input (especially from HTTP requests!) to a WHERE clause.
These changes eliminate the need for dynamic SQL, which can be insecure and difficult to maintain.

Query doesn't update table when it is run form Python code

When I run a query from sqlite browser the table get updated but when I use same query from Python the database won't get updated:
def updateDB (number, varCheck=True):
conn = sqlite3.connect(db)
c = conn.cursor()
i = 1
for each_test in number:
c.execute("UPDATE table1 SET val='%s' WHERE amount='%s' AND rank='%s'" % (each_test , str(i), 'rank2'))
i += 1
conn.commit()
conn.close()
return True
How can I fix the issue? I run python code as sudo.

In the past, I had similar issues while creating sql queries. I doubt if your sql query is being correctly formatted. The % string interpolation method can be a problem. Try using the .format() on the sql query string. PEP3101 explains the same about using .format() instead of % operator for string interpolation.
val='"' + each_test + '"'
amount = '"' + str(i) + '"'
rank= '"' + "rank2" + '"'
sql_qeury = "UPDATE table1 SET val={val} WHERE amount={amount} AND rank={rank}".format(val=val,amount=amount,rank=rank)

Python, MySQL: Getting Null Inserts, but print() is giving value, and SQL is valid?

In the following code:
print(str(processedEmails))
print(campaignId)
returns values I was expecting.
What I'm trying to do (why I ran print() statements to check):
cursor.execute('UPDATE campaigns SET campaign_finish_date = (NOW()) AND queue_size =' + str(processedEmails) + ' WHERE id=' + campaignId)
checking via phpMyAdmin:
NOW() = 0000-00-00 00:00:00.000000
campaignId = 0 (what I set as default)
Values not transferred.
What am I doing wrong?

Assuming you're using MySQLdb module, you need to commit() the query if autocommit() is False (default).
See this.
Edit #1:
Then grant that the query is being successfully executed. Have you tried to execute that query via phpMyAdmin? Does it work as expected?
I've noticed that you've a AND instead a comma (',') on your update query:
You've this:
cursor.execute('UPDATE campaigns SET campaign_finish_date = (NOW()) AND queue_size =' + str(processedEmails) + ' WHERE id=' + campaignId)
Instead of this:
cursor.execute('UPDATE campaigns SET campaign_finish_date = (NOW()), queue_size =' + str(processedEmails) + ' WHERE id=' + campaignId)