Formatting data to JSON - json

I'm getting data from PostgreSQL using python
import psycopg2
import json
conn = psycopg2.connect(database="testdb", user="openpg", password="openpgpwd", host="127.0.0.1", port="5432")
print "Opened database successfully"
cur = conn.cursor()
cur.execute("SELECT id, name, address, salary from COMPANY")
rows = cur.fetchall()
print "Operation done successfully";
Then i try to format this data to JSON format: with the following command:
result = json.dumps(rows)
for row in result:
print row
but i get each caracteres of the ID, Name, address, ... in a separate row:
for example : name= abc
when execute the script i get:
a
b
c

Your result (rows) is a string (that's what json.dumps() returns). That's why when you iterate thru rows, you are iterating and printing each character.
just do print rows instead

json.dumps() returns a string, so iterating over returns each character.
To get a stream, use json.dump()

Related

Python 3 psycopg2 COPY from stdin failed: error in .read()

I am trying to apply the code found on this page, in particular part 'Copy Data from String Iterator' of the Table of Contents, but run into an issue with my code.
Since not all lines coming from the generator (here log_lines) can be imported into the PostgreSQL database, I try to filter the correct lines (here row) using itertools.filterfalse like in the codeblock below:
def copy_string_iterator(connection, log_lines) -> None:
with connection.cursor() as cursor:
create_staging_table(cursor)
log_string_iterator = StringIteratorIO((
'|'.join(map(clean_csv_value, (
row['date'],
row['time'],
row['cs_uri_query'],
row['s_contentpath'],
row['sc_status'],
row['s_computername'],
...
row['sc_substates'],
row['s_port'],
row['cs_version'],
row['c_protocol'],
row.update({'cs_cookie':'x'}),
row['timetakenms'],
row['cs_uri_stem'],
))) + '\n')
for row in filterfalse(lambda line: "#" in line.get('date'), log_lines)
)
cursor.copy_from(log_string_iterator, 'log_table', sep = '|')
When I run this, cursor.copy_from() gives me the following error:
QueryCanceled: COPY from stdin failed: error in .read() call
CONTEXT: COPY log_table, line 112910
I understand why this error happens, it is because in the test file I use there are only 112909 lines that meet the filterfalse condition. But why does it try to copy line 112910 and throw the error and not just stop?
Since Python doesn't have a coalescing operator, add something like:
(map(clean_csv_value, (
row['date'] if 'date' in row else None,
:
row['cs_uri_stem'] if 'cs_uri_stem' in row else None,
))) + '\n')
for each of your fields so you can handle any missing fields in the JSON file. Of course the fields should be nullable in the db if you use None otherwise replace with None with some default value for that field.

how to upload whole text of a file in a row in mysql through terminal

How to upload whole text of a text file in a row in database, the text gets divided and is stored in subsequent rows.
This is the code of my SQL file, database name is info containing table named info having two columns des1 and des2 having field VARCHAR(3000):
use info;
INSERT INTO info (des1) VALUES (LOAD_FILE('eng.txt'));
select * from(info);
I am getting following output:
des1 des2
NULL NULL
I also attatched an image showing output
I expect all of the text in the file to be in a single row of the database, this has to be done in terminal
There might be a problem with how you form the string that is to be inserted. You can do it easily by the help of a programming language.
I am providing a simple solution that would work in Python.
import mysql.connector
mydb = mysql.connector.connect(
host="localhost",
user="root",
passwd="password",
database="db"
)
def fileReadToString(filename):
result = ""
with open(filename, "r") as ins:
for line in ins:
result +=(line)
return result
file = fileReadToString('eng.txt')
mycursor = mydb.cursor()
sql = "INSERT INTO info VALUES (%s)"
val = (file)
mycursor.execute(sql, val)
mydb.commit()
print(mycursor.rowcount, "done")
LOAD DATA INFILE is for structured data. For unstructured data use LOAD_FILE():
INSERT INTO info (des1) VALUES (LOAD_FILE('eng.txt'))

How can I remove "u" in python 2.7.13, while fetching data from sqlite3 and displaying it with a tkmessagebox

This is the code I am executing to extract data but the unicode's "u"
is not getting removed
cur=con.cursor()
e1=self.entry1.get()
e2=self.entry2.get()
e3=self.entry3.get()
e4=self.entry4.get()
cur.execute("insert into student13 values(?,?,?,?)",(e1,e2,e3,e4))
con.commit()
cur.execute("select * from student13")
ar=cur.fetchall()
>#fetching data from database
tkMessageBox.showinfo("records",ar)
You could try the ".encode" function
ar = u'unicode string'
ar = ar.encode('ascii')

odoo 9 migrate binary field db to filestore

Odoo 9 custom module binary field attachment=True parameter added later after that new record will be stored in filesystem storage.
Binary Fields some old records attachment = True not used, so old record entry not created in ir.attachment table and filesystem not saved.
I would like to know how to migrate old records binary field value store in filesystem storage?. How to create/insert records in ir_attachment row based on old records binary field value? Is any script available?
You have to include the postgre bin path in pg_path in your configuration file. This will restore the file store that contains the binary fields
pg_path = D:\fx\upsynth_Postgres\bin
I'm sure that you no longer need a solution to this as you asked 18 months ago, but I have just had the same issue (many gigabytes of binary data in the database) and this question came up on Google so I thought I would share my solution.
When you set attachment=True the binary column will remain in the database, but the system will look in the filestore instead for the data. This left me unable to access the data from the Odoo API so I needed to retrieve the binary data from the database directly, then re-write the binary data to the record using Odoo and then finally drop the column and vacuum the table.
Here is my script, which is inspired by this solution for migrating attachments, but this solution will work for any field in any model and reads the binary data from the database rather than from the Odoo API.
import xmlrpclib
import psycopg2
username = 'your_odoo_username'
pwd = 'your_odoo_password'
url = 'http://ip-address:8069'
dbname = 'database-name'
model = 'model.name'
field = 'field_name'
dbuser = 'postgres_user'
dbpwd = 'postgres_password'
dbhost = 'postgres_host'
conn = psycopg2.connect(database=dbname, user=dbuser, password=dbpwd, host=dbhost, port='5432')
cr = conn.cursor()
# Get the uid
sock_common = xmlrpclib.ServerProxy ('%s/xmlrpc/common' % url)
uid = sock_common.login(dbname, username, pwd)
sock = xmlrpclib.ServerProxy('%s/xmlrpc/object' % url)
def migrate_attachment(res_id):
# 1. get data
cr.execute("SELECT %s from %s where id=%s" % (field, model.replace('.', '_'), res_id))
data = cr.fetchall()[0][0]
# Re-Write attachment
if data:
data = str(data)
sock.execute(dbname, uid, pwd, model, 'write', [res_id], {field: str(data)})
return True
else:
return False
# SELECT attachments:
records = sock.execute(dbname, uid, pwd, model, 'search', [])
cnt = len(records)
print cnt
i = 0
for res_id in records:
att = sock.execute(dbname, uid, pwd, model, 'read', res_id, [field])
status = migrate_attachment(res_id)
print 'Migrated ID %s (attachment %s of %s) [Contained data: %s]' % (res_id, i, cnt, status)
i += 1
cr.close()
print "done ..."
Afterwards, drop the column and vacuum the table in psql.

Julia - Rewriting a CSV

Complete Julia newbie here.
I'd like to do some processing on a CSV. Something along the lines of:
using CSV
in_file = CSV.Source('/dir/in.csv')
out_file = CSV.Sink('/dir/out.csv')
for line in CSV.eachline(in_file)
replace!(line, "None", "")
CSV.writeline(out_file, line)
end
This is in pseudocode, those aren't existing functions.
Idiomatically, should I iterate on 1:CSV.countlines(in_file)? Do a while and check something?
If all you want to do is replace a string in the line, you do not need any CSV parsing utilities. All you do is read the file line by line, replace, and write. So:
infile = "/path/to/input.csv"
outfile = "/path/to/output.csv"
out = open(outfile, "w+")
for line in readlines(infile)
newline = replace(line, "a", "b")
write(out, newline)
end
close(out)
This will replicate the pseudocode you have in your question.
If you need to parse and read the csv field by field, use the readcsv function in base.
data=readcsv(infile)
typeof(data) #Array{Any,2}
This will return the data in the file as a 2 dimensional array. You can process this data any way you want, and write it back using the writecsv function.
for i in 1:size(data,1) #iterate by rows
data[i, 1] = "This is " * data[i, 1] # Add text to first column
end
writecsv(outfile, data)
Documentation for these functions:
http://docs.julialang.org/en/release-0.5/stdlib/io-network/?highlight=readcsv#Base.readcsv
http://docs.julialang.org/en/release-0.5/stdlib/io-network/?highlight=readcsv#Base.writecsv