I have an application in C# that uses System.Data.SQLite. In my case I use a recent version of SQL Lite database, by now I can see that the new versión has released, and int sqlite.org webpage says that is recommended to upgrade the database.
My question is how to upgrade without lost the information in my actual database.
How can I chech the version of the data
Thanks.
EDIT: what I mean is when I create a new database with the sqlite3 library, I guess that the database file, my database.db has a version. When I update the sqlite3 library, I am update the sqlite3 command line, but the database file still has the version that had when I created it.
So if in the new versions for example add new features to the database, for example triggers, foreign keys and so on, if I am not wrong, this features must be in the database file, not in the sqlite3 library, because when I access to the database for example with entity framework, I don't use sqlite3 library, I use System.SQLite.Data library.
am I wrong? the datafile is never update and only the library can be updated?
Thanks.
Upgrading the SQLite library will not have any effect on your database file.
Changes like foreign keys do not affect the database file.
The last change that affected the file format was a long time ago.
Related
I have a huge problem... I am developing desktop app with SQLite but during copy/paste process I lost a power and process was terminated so base was lost. However, I found a way to recover it but base is encrypted. When I try to open connection using conn.Open(); I get this error. If I try to open it with DB Browser for SQLite it asks me a SQLCipher encryption password so it seams to me that data is lost..
Is there any default password ?
Why did this happen and how to prevent it from happening again ?
What can I do ?
Thanks in advance.
Also check that SQLite version you're "connecting" with aligns with the DB file version.
For example, here's a DB file written by SQLite version 3+:
$ file foobar.db
foobar.db: SQLite 3.x database, last written using SQLite version 3027002
And here I also have 2 versions of sqlite:
$ sqlite -version
2.8.17
$ sqlite3 -version
3.27.2 2019-02-25 16:06:06 bd49a8271d650fa89e446b42e513b595a717b9212c91dd384aab871fc1d0alt1
Obviously in hindsight, opening foobar.db with sqlite version 2 will fail, yielding the same error message:
$ sqlite foobar.db
Unable to open database "foobar.db": file is encrypted or is not a database
But all is good with the correct version:
$ sqlite3 foobar.db
SQLite version 3.27.2 2019-02-25 16:06:06
Enter ".help" for usage hints.
sqlite>
sqlite> .databases
main: /tmp/foobar.db
sqlite>
The error message is a catch-all, simply meaning that the file format was not recognized.
Ok, finally found a solution that works so posting the answer if anybody will have same trouble as I did..
First of all, use good recover software. For repairing the database I found 3 solutions that work without backup :
Open corrupted database using DB Browser an Export Database to SQL. Name it however you want. Then, create new database and import database from SQL.
There is software that repairs corrupted databases. Download one and use it to repair the database.
Download "sqlite3" from sqlite.org and in command line navigate to folder where "sqlite3" is unzipped. Then try to dump the entire database with .dump, and use those commands to create a new database:
sqlite3 corrupt_table_name.sqlite ".dump" | sqlite3 new.sqlite
I had the same error when I was trying to access a db dump in another system compared to compared to where it was obtained. When I tried to open on a dev machine, it threw the reported error in this thread:
$ sqlite3 db_dump.sqlite .tables
Error: file is encrypted or is not a database
This turned out to be due to the differences in the sqlite version between those systems. This dev system version was 3.6.20.
The version on the production system was 3.8.9. Once I had the sqlite3 upgraded to same version, I was able to access all its data. I am just showing below the tables are displayed as expected:
# sqlite3 -version
3.8.9
# sqlite3 db_dump.sqlite .tables
capture diskio transport
consumer filters processes
This error is rather misleading to begin with, though.
If you've interacted with the database at some point while specifying journal_mode = WAL, and then later try to use the database from a client that does not support WAL (< v3.7.0), this error can also come up.
As noted in the SQLite documentation under Backwards Compatibility, to resolve that without having to recreate the database, explicitly set the journal mode to DELETE:
PRAGMA journal_mode=DELETE;
Your database did not become encrypted (this is only one of the two options in the error message).
Your data recovery tool did not recover the correct data; what you have in the file is something else.
You have to restore the database file from the backup.
The issue is with sqlcipher version upgrade in my case, Whenever I update my pod it automatically upgrade the sqlcipher and the error occurred.
For a quick fix just manually add the SDK instead of Pod install. And for a proper solution use this link GitHub Solution
I am creating an app it takes data from the server and storing it in SQLite database but each time I run the app the data gets append in the database. I tried onUpgrade() method to drop table and create a new one, but its not working because db_version is the same. But if I change the version manually then its working... but I want solution so that my version changes each time automatically when I run the app....
OR if there is an another alternative please share it....
You are probably didn't understand what is database Upgrade. In two words you upgrade the version of your database when your DB model changed, not the data!
To clear your database for testing purposes use sqlite DROP TABLE or physically delete the file!
If you upgrade the version of the database each time your app starts - you will lose all the database data each time your app starts, so why do you need the database ?
I have been developing locally for some time and am now pushing everything to production. Of course I was also adding data to the development server without thinking that I hadn't reconfigured it to be Postgres.
Now I have a SQLite DB who's information I need to be on a remote VPS on a Postgres DB there.
I have tried dumping to a .sql file but am getting a lot of syntax complaints from Postgres. What's the best way to do this?
For pretty much any conversion between two databases the options are:
Do a schema-only dump from the source database. Hand-convert it and load it into the target database. Then do a data only dump from the source DB in the most compatible form of SQL dump it offers. Try loading that into the target DB. When you hit problems, script transformations to the dump using sed/awk/perl/whatever and try again. Repeat until it loads and the results match.
Like (1), hand-convert the schema. Then write a script in your preferred language that connects to both databases, SELECTs from one, and INSERTs into the other, possibly with some transformations of data types and representations.
Use an ETL tool like Talend or Pentaho to connect to both databases and convert between them. ETL tools are like a "somebody else already wrote it" version of (2), but they can take some learning.
Hope that you can find a pre-written conversion too. Heroku one called sequel that will work for SQLite -> PostgreSQL; is it available without Heroku and able to function without all the other Heroku infrastructure and code?
After any of those, some post-transfer steps like using setval() to initialize sequences is typically required.
Heroku's database conversion tool is called sequel. Here are the ruby gems you need:
gem install sequel
gem install sqlite3
gem install pg
Then this worked for me for a sqlite database file named 'tweets.db' in the current working directory:
sequel -C sqlite://tweets.db postgres://pgusername:pgpassword#localhost/pgdatabasename
PostgreSQL supports "foreign data wrappers", which allow you to directly access any data source through the DB, including sqlite. Even up to automatically importing the schema. You can then use create table localtbl as (select * from remotetbl) to get your data into the actual PG storage.
https://wiki.postgresql.org/wiki/Foreign_data_wrappers
https://github.com/pgspider/sqlite_fdw
I am working on a firm application in which I need to create a local database on my device.
I create my local database through create statement[ It works well]
Then I use that file and perform insert operation through fire-fox sqlite plugin, I need to insert aprox 2000 rows at a time so I can not use code. I just run insert manually through sqlite plugin in fir-fox.
After that I just use that file in my place of my local database.
When I run select query through my code, It show Exception:java.lang.Exception: Exception: In create or prepare statement in DBnet.rim.device.api.database.DatabaseException: SELECT distinct productline FROM T_Electrical ORDER BY productline: file is encrypted or is not a database
I got the solution of this problem, I was doing a silly mistake by creating a file manually by right click in my RES folder, that is not correct. We need to create the database completely from SQlite plugin, then it will work fine. "Create data base from SQLITE(FIle too) and perform insertion operation from SQLITE, then it will work fine"
This is very rare problem, but i think it might be helpful for someone like me....!:)
You should check to see if there is a version problem between the SQLite used by your Firefox installation and that on the BlackBerry. I think I had the same error when I tried to build a database file with SQLite version 2.
You also shouldn't need to create the database file on the device. To create large tables I use a Ubuntu machine and the sqlite3 command line. Create the file, create the tables, insert the data and build indexes. Then I just copy the file onto the device in the proper directory.
For me it was a simple thing. One password was set to that db. I just used it and prolem got solved.
How to manage database changes while upgrading desktop applications?
We have a SQLite database for one of our desktop apps. The uninstaller keeps the database to be used by the next install. But what if the next install has an updated version? How to keep the data but upgrade the tables?
We use .NET and Linq2sql
Here is how I do this:
In my code I define the version of the database
#define DB_VERSION 2
This version number is incremented every time I make a change to the code that 'breaks' the database ( makes an incompatible change to the schema or the semantics of the db contents )
When the code creates a new database, it executes this SQL command
QueryFormat(L"PRAGMA SCHEMA_VERSION = %d;",DB_VERSION);
Note that this must be AFTER all CREATE TABLE commands have been executed, otherwise sqlite increments SCHEMA_VERSION.
When the code opens an existing database, the first thing it does is
Query(L"PRAGMA schema_version;")
The SCHEMA_VERSION that is returned from this query is compared with the DB_VERSION. If they do not match, then the database was created by a different software version. What happens next depends on the details of what you need. Typically:
database was created by a more recent software: inform user and exit
database was created by older software for which there is an upgrade: offer user option to run upgrade code, or re-initialize database
database was created by older software with no upgrade: offer user option to re-initialize database or exit.
The details of how the upgrade code works depends very much on what you need. In general open the old database AND open a new empty database. Read the old tables, convert the data as required, and write to the new database. Close the dbs. Delete the old db. Rename the new db to the standard db name. Open the new db.
If nothing else, the output of echo .dump | sqlite my_database.sqlite is designed to be extremely portable, even to non-SQLite databases.
Or, if I'm misreading your question, you may want alter table.