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migrate autonumber columns from access to sqlite

I'm trying to migrate the database for an existing application from access to SQLite. The application uses Autonumbers to generate unique IDs in Access and some tables reference rows from other tables by these unique IDs.
What's a good way to migrate these and keep this functionality intact?
From what I've read, SQLite uses Auto indexing for this. How would I create the links between the tables? Do I have to search the other tables for the row with that unique ID and replace the reference with the SQL generated ID?
example:
table 1, has a column linkedID with a row with the value {7F99297A-DE91-4BD6-9ED8-FC13D668CDA2}, which is linked to a row in table 2 with primaryKey {7F99297A-DE91-4BD6-9ED8-FC13D668CDA2}.

Well, there not really a automated way to do this.
but, what I do to migrate data?
I setup a linked table in Access. Double check if that linked table works (you need to install the odbc driver).
Assuming you have a working linked table?
Then you can do this to export the Access table in VBA to sqlite.
Dim LocalTable As String ' name of local table link
Dim ServerTable As String ' name of table on SQL Lite
LocalTable = "Table1"
ServerTable = "TableSLite"
Dim strCon As String
strCon = CurrentDb.TableDefs("Test1").Connect
' above is a way to steal and get a working connection from a valid
' working linked table (I hate connection strings in code)
Debug.Print strCon
DoCmd.TransferDatabase acExport, "ODBC Database", strCon, acTable, LocalTable, ServerTable
Debug.Print "done export of " & LocalTable
That will get you the table in sqlite. But, there are no DDL (data definition commands) in sqlite to THEN change that PK id from Access to a PK and autonumber.
However, assuming you say have "db browser"?
Then simple export the table(s) as per above.
Now, in db browrser, open up the table, and choose modify, and simple check the AI (auto increemnt, and then PK settings - in fact if you check box AI, then the PK useally selects for you. So, after I done the above export. (and you should consider close down Access - since you had/have linked tables).
So, in db browser, we now do this:
so, for just a few tables, the above is not really hard.
However, the above export (transfer) of data does not set the PK, and auto increment for you.
If you need to do this with code, and this is not a one time export/transfer, then I don't have a good solution.
Unfortantly, SqlLite does NOT allow a alter table command to set PK and set auto increment (if that was possbile, then after a export, you could execute the DDL command in sqlite (or send the command from your client software) to make this alteration.
I not sure if sql lite can spit out the "create table" command that exists for a given table (but, I think it can). So, you might export the schema, get the DDL command, modify that command, drop the table, re-run the create table command (with current PK and auto increment), and THEN use a export or append query in Access.
But, transfer of the table(s) in question can be done quite easy as per above, but the result(s) do not set nor include the PK setting(s) for you.
However, if this is one time export? Then export of tables - and even the dirty work of figuring out the correct data types to be used?
The above works well - but you have to open up the tables in a tool like say db browser, and then set PK and auto increment.
I do the above quite often for transfer of Access tables to sqlLite tables, but it does then require some extra steps to setup the PK and auto increment.
Another possbile way if this had to be done more then one time?
I would export as per above, and then add the PK (and auto increment).
I would then grab say the 8 tables create commands from sqlLite, and save those create table commands in the client software.
then you execute the correct create table command, and then do a append query from Access. So, it really depends if this is a one time export, or this process of having to create the table(s) in sqlLite is to occur over and over.

Comparing my input with values in my database

i recently got into programming and i'm having a hard time understanding how things work SO please help me. I created a database using mySQL and i filled it with some data (10 values called ID numbers),if i want the user to enter a value (his ID number) in my program (I'm using python) and i want my program to take this value and compare it with the values in my database then return "Already exists" if any of the values in my DB is equal to the value the user put, how do i do that ? and should i keep using python ? or is there anything that you would recommend to access/work on my databse ?
Thank you in advance,

You should first follow this mini-tutorial to connect Python with MySQL and be able to run MySQL commands in python.
Then it should be as simple as selecting all of the id's from the table and checking if any match with the user input. To select all of the ID's you'd use something like this (change it to match your database):
mycursor.execute("SELECT * FROM ID")
You can see a few more examples here.
I hope this helps.

preventing updation of specific columns in sqlite from python

i am developing a twisted app which interacts with a sqlite backend, in the sqlite db there is a users table of which certain columns should not be updated if they already contain a value.
one way of doing this would be to check the user table before each insert for existence of values in the columns of interest and proceed accordingly , but this will be a performance killer and people familiar with twisted will know how cumbersome this can be, can someone suggest a better way of doing this .
TIA

Try the INSERT OR IGNORE variation of the INSERT statement.

Ways to give a SQLite a variable name

I am tracking changes made to a levels in a game. The way I currently track changes is in a sqlite database. Each level is supposed to have its own database, as just one database for all the levels would provide complications when adding and deleting levels. So for each level, I want a database that has the same name as that level. SO that changes made to level "foo" get written to database "foo". I don't need to edit the tables just the actual name of the database. I guess now that I could just use a file renaming function in python, but I would like to know if there is any way to change names from the start.
Heres an example:
connection = sqlite.connect('\database\foo.db')
cursor = connection.cursor()
Where foo is the variable

You'll need to post some code for us to answer this completely.
You can use the ALTER TABLE command to rename the tables within your database, you can rename your sqlite db file on disk if you close it first, and you can use a variable in your python code to represent the name of the DB you're using. But you need to be more specific if you want a more specific answer.

Using SQLite in a Python program

I have created a Python module that creates and populates several SQLite tables. Now, I want to use it in a program but I don't really know how to call it properly. All the tutorials I've found are essentially "inline", i.e. they walk through using SQLite in a linear fashion rather than how to actually use it in production.
What I'm trying to do is have a method check to see if the database is already created. If so, then I can use it. If not, an exception is raised and the program will create the database. (Or use if/else statements, whichever is better).
I created a test script to see if my logic is correct but it's not working. When I create the try statement, it just creates a new database rather than checking if one already exists. The next time I run the script, I get an error that the table already exists, even if I tried catching the exception. (I haven't used try/except before but figured this is a good time to learn).
Are there any good tutorials for using SQLite operationally or any suggestions on how to code this? I've looked through the pysqlite tutorial and others I found but they don't address this.

Don't make this more complex than it needs to be. The big, independent databases have complex setup and configuration requirements. SQLite is just a file you access with SQL, it's much simpler.
Do the following.
Add a table to your database for "Components" or "Versions" or "Configuration" or "Release" or something administrative like that.
CREATE TABLE REVISION(
RELEASE_NUMBER CHAR(20)
);
In your application, connect to your database normally.
Execute a simple query against the revision table. Here's what can happen.
The query fails to execute: your database doesn't exist, so execute a series of CREATE statements to build it.
The query succeeds but returns no rows or the release number is lower than expected: your database exists, but is out of date. You need to migrate from that release to the current release. Hopefully, you have a sequence of DROP, CREATE and ALTER statements to do this.
The query succeeds, and the release number is the expected value. Do nothing more, your database is configured correctly.

AFAIK an SQLITE database is just a file.
To check if the database exists, check for file existence.
When you open a SQLITE database it will automatically create one if the file that backs it up is not in place.
If you try and open a file as a sqlite3 database that is NOT a database, you will get this:
"sqlite3.DatabaseError: file is encrypted or is not a database"
so check to see if the file exists and also make sure to try and catch the exception in case the file is not a sqlite3 database

SQLite automatically creates the database file the first time you try to use it. The SQL statements for creating tables can use IF NOT EXISTS to make the commands only take effect if the table has not been created This way you don't need to check for the database's existence beforehand: SQLite can take care of that for you.
The main thing I would still be worried about is that executing CREATE TABLE IF EXISTS for every web transaction (say) would be inefficient; you can avoid that by having the program keep an (in-memory) variable saying whether it has created the database today, so it runs the CREATE TABLE script once per run. This would still allow for you to delete the database and start over during debugging.

As #diciu pointed out, the database file will be created by sqlite3.connect.
If you want to take a special action when the file is not there, you'll have to explicitly check for existance:
import os
import sqlite3
if not os.path.exists(mydb_path):
#create new DB, create table stocks
con = sqlite3.connect(mydb_path)
con.execute('''create table stocks
(date text, trans text, symbol text, qty real, price real)''')
else:
#use existing DB
con = sqlite3.connect(mydb_path)
...

Sqlite doesn't throw an exception if you create a new database with the same name, it will just connect to it. Since sqlite is a file based database, I suggest you just check for the existence of the file.
About your second problem, to check if a table has been already created, just catch the exception. An exception "sqlite3.OperationalError: table TEST already exists" is thrown if the table already exist.
import sqlite3
import os
database_name = "newdb.db"
if not os.path.isfile(database_name):
print "the database already exist"
db_connection = sqlite3.connect(database_name)
db_cursor = db_connection.cursor()
try:
db_cursor.execute('CREATE TABLE TEST (a INTEGER);')
except sqlite3.OperationalError, msg:
print msg

Doing SQL in overall is horrible in any language I've picked up. SQLalchemy has shown to be easiest from them to use because actual query and committing with it is so clean and absent from troubles.
Here's some basic steps on actually using sqlalchemy in your app, better details can be found from the documentation.
provide table definitions and create ORM-mappings
load database
ask it to create tables from the definitions (won't do so if they exist)
create session maker (optional)
create session
After creating a session, you can commit and query from the database.

See this solution at SourceForge which covers your question in a tutorial manner, with instructive source code :
y_serial.py module :: warehouse Python objects with SQLite
"Serialization + persistance :: in a few lines of code, compress and annotate Python objects into SQLite; then later retrieve them chronologically by keywords without any SQL. Most useful "standard" module for a database to store schema-less data."
http://yserial.sourceforge.net

Yes, I was nuking out the problem. All I needed to do was check for the file and catch the IOError if it didn't exist.
Thanks for all the other answers. They may come in handy in the future.