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SQLITE multiple files

Sorry about this unprofessional question but I'm kinda new to sqlite but I was wondering if there's any way I can open two files in same python command db = sqlite3.connect('./cogs/database/users.sqlite')
when I open this in my command it doesn't allow me to do same thing in the same command to open another file so for example
open db = sqlite3.connect('./cogs/database/users.sqlite') and read something from it if so
open db = sqlite3.connect('./cogs/database/anotherfile.sqlite') and insert to it
but it always accepts first file only and ignore second file

Assign db1 so it connects to users.sqlite,
and db2 so it connects to anotherfile.sqlite.
Then you can e.g. SELECT from one
and INSERT into the other,
with a temp var bridging the two.

Sqlite databases are single file based, so no - sqlite3.connect builds a connection object to a single data base file.
Even if you build two connection objects, you can't execute queries across them.
If you really need the data from two files at a time you need to merge that data into one data - or don't use sqlite.

You can execute queries across two SQLite files, but you will need to execute an ATTACH command on the first connection cursor.
conn = sqlite3.connect("users.sqlite")
cur = conn.cursor()
cmd = "ATTACH DATABASE 'anotherfile.sqlite' AS otra"
try:
cur.execute(cmd)
query = """
SELECT
t1.Id, t1.Name, t2.Address
FROM personnel t1
LEFT JOIN otra.location t2
ON t2.PersonId = t1.Id
WHERE t1.Status = 'current'
ORDER BY t1.Name;
"""
cur.execute(query)
rows = cur.fetchall()
except sqlite3.Error as err:
do_something_with(err)

Is there a SQLite equivalent to COPY from PostgreSQL?

I have local tab delimited raw data files "...\publisher.txt" and "...\field.txt" that I would like to load into a local SQLite database. The corresponding tables are already defined in the local database. I am accessing the database through the python-sql library in an ipython notebook. Is there a simple way to load these text files into the database?
CLI command 'readfile' doesn't seem to work in python context:
INSERT INTO Pub(k,p) VALUES('pubFile.txt',readfile('pubFile.txt'));
Throws error:
(sqlite3.OperationalError) no such function: readfile
[SQL: INSERT INTO Pub(k,p) VALUES('pubFile.txt',readfile('pubFile.txt'));]
(Background on this error at: http://sqlalche.me/e/e3q8)

No, there isn't such a command in SQLite (any longer). That feature was removed, and has been replaced by the SQLite CLI's .import statement.
See the official documentation:
The COPY command is available in SQLite version 2.8 and earlier. The COPY command has been removed from SQLite version 3.0 due to complications in trying to support it in a mixed UTF-8/16 environment. In version 3.0, the command-line shell contains a new command .import that can be used as a substitute for COPY.
The COPY command is an extension used to load large amounts of data into a table. It is modeled after a similar command found in PostgreSQL. In fact, the SQLite COPY command is specifically designed to be able to read the output of the PostgreSQL dump utility pg_dump so that data can be easily transferred from PostgreSQL into SQLite.
A sample code to load a text file into an SQLite database via the CLI is as below:
sqlite3 test.db ".import "test.txt" test_table_name"

You may read the input file into a string and then insert it:
sql = "INSERT INTO Pub (k, p) VALUES ('pubFile.txt', ?)"
with open ("pubFile.txt", "r") as myfile:
data = '\n'.join(myfile.readlines())
cur = conn.cursor()
cur.execute(sql, (data,))
conn.commit()

sqlite file is shown empty in python and r

I am trying to open a .sqlite3 file in python but I see no information is returned. So I tried r and still get empty for tables. I would like to know what tables are in this file.
I used the following code for python:
import sqlite3
from sqlite3 import Error
def create_connection(db_file):
""" create a database connection to the SQLite database
specified by the db_file
:param db_file: database file
:return: Connection object or None
"""
try:
conn = sqlite3.connect(db_file)
return conn
except Error as e:
print(e)
return None
database = "D:\\...\assignee.sqlite3"
conn = create_connection(database)
cur = conn.cursor()
rows = cur.fetchall()
but rows are empty!
This is where I got the assignee.sqlite3 from:
https://github.com/funginstitute/downloads
I also tried RStudio, below is the code and results:
> con <- dbConnect(drv=RSQLite::SQLite(), dbname="D:/.../assignee")
> tables <- dbListTables(con)
But this is what I get

first make sure you provided correct path on your connection string to the sql
light db ,
use this conn = sqlite3.connect("C:\users\guest\desktop\example.db")
also make sure you are using the SQLite library in the unit tests and the production code
check the types of sqllite connection strings and determain which one your db belongs to :
Basic
Data Source=c:\mydb.db;Version=3;
Version 2 is not supported by this class library.
SQLite
In-Memory Database
An SQLite database is normally stored on disk but the database can also be
stored in memory. Read more about SQLite in-memory databases.
Data Source=:memory:;Version=3;New=True;
SQLite
Using UTF16
Data Source=c:\mydb.db;Version=3;UseUTF16Encoding=True;
SQLite
With password
Data Source=c:\mydb.db;Version=3;Password=myPassword;
so make sure you wrote the proper connection string for your sql lite db
if you still cannot see it, check if the disk containing /tmp full otherwise , it might be encrypted database, or locked and used by some other application maybe , you may confirm that by using one of the many tools for sql light database ,
you may downliad this tool , try to navigate directly to where your db exist and it will give you indication of the problem .
download windows version
Download Mac Version
Download linux version
good luck

Periodically outputting SQL table to a file

I'm trying to write a python script that continuously updates a file with the contents of a table in my database.
The table in the database is changing continuously, so I need to periodically update this file as well. I could do a select * query and get all the entries, but what would be great is if I could get the output table when applying the formatting of .mode column and .headers on.
What I've tried to do is create a SQL cursor and execute ".output file.txt", but that gives me an sqlite syntax error. I tried to call from the script os.sys("sqlite3 dbname.db 'select * from table;' > file.txt") but that doesn't seem to work either ("'module' object is not callable").
Is there a way for me to get the nicely formatted sqlite table?

import subprocess
f=open('file.txt','w')
subprocess.call(['sqlite3', 'dbname.db', '-csv', 'select * from table'], stdout=f)

Database not consistent when accessed from different source files

I have a program in Python composed of 4 source files. One of them is the main file which imports the other 3. As I work with a small Sqlite database, I am creating tables in one of the "secondary" source files, but when I access the database again from the main source file, the tables just populated before are empty.
Can I save the tables' content in a more consistent way? I am quite surprised with what is happening.
So in the main file I typed:
conn = sqlite3.connect("bayes.db")
cur = conn.cursor()
cur.execute("select count(*) from TableA")
print cur.fetchone()
The result is 0 (rows).
Just before, in another source file I do the same thing and get size=8 of TableA.

You must call the commit function in order to save your changes in the database. You can see the full documentation here: http://docs.python.org/2/library/sqlite3.html#sqlite3.Connection.commit