I am working on a iOS mobile application using Xcode as the IDE and Swift as the language of choice. I added a column to the SQLite database that interacts with my application but unfortunately when I attempt to perform any database operations through the application the column is not recognized.
The following error is sent:
DB Error: 1 "table xyz has no column named column_name"
When I added the column I also increased the database version or user_version in SQLiteStudio.
Is there something else I should be doing to cause the application to recognize the changes? I know uninstalling and reinstalling would work but that is not an option of course as I cannot lose the data currently housed in the database. My other idea was to put all the data in temporary variables or something like that, drop and recreate the tables and reinsert the data. I wasn't sure if this was a good course of action though. Any help with this is appreciated.
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I am really sorry to ask a simple question like this, but it is getting frustrating. I installed neo4j 4.0.4 on my Windows machine, created a new project as shown in the official tutorial video and set a password for my local graph. Funnily, the tutorial video ends after setting the password and opening the browser not showing how to perform Cypher queries on this newly created database. In neo4j Desktop my database is shown correctly and it seems to be up and running.
However, when I try to connect to this database via the browser, I do not see the database at all. It is so confusing when connecting to the server to specify a username and password, if you only need to set a password for your database?! The default neo4j user can see the system and default database but not my project database. In addition, I cannot link files from the project directory in Cypher queries. I tried to disable authentication, but it did not help at all.
When I issue SHOW DATABASES command, it does not list my database as well.
Update / Edit:
Seems I misunderstood the concept of projects. Every database is named neo4j - default, regardless of the name specified in the project ?!. However, I still cannot access project files. So far, I copied the files manually in the database directory under "imports". But I guess that is not the intended way.
After importing data to this default database, it still shows no data in the project itself.
Data files in the imports directory are not automatically imported into the DB. That is because neo4j has no idea how you want to store that data as nodes and relationships.
So, it is up to you to determine your desired data model, and then write the appropriate code to enforce that data model.
You can take a look at this page to learn about how to import CSV data (probably the most commonly used import data format).
I am creating a small tool to update database table. So i want to add columns to table using embedded database (using alias path- without running Nxserver) database. I did it successfully but table can't be opened from Enterprise manager.
It says "incompatible stream". I can load table to a dbgrid using embedded database.
it might be a version issue between embedded database and server. But how can i do this for any version?
Restructure upgrades a table file to the table version of the server engine that performed the restructure. In this case the server engine that's embedded in your application.
If this table version is newer than the table version supported by the nxServer or EM (if using the internal server) you are later using to try and access this table, then you may get this error.
If you are going to access the table through a specific nxServer later, you should be using that server to perform the restructure, not the embedded engine in your program.
At the early stages of development, where data retention is no issue and experimental changes to the schema are expected to be numerous, is there a way to avoid migration? Namely, just to dump the database and start over each time.
Everything I try leads to the error: "The model used to open the store is incompatible with the one used to create the store".
Lightweight migration looks do-able, but I'll end up lots of unwanted versions and messy code. I'd also like to experiment with relationships (no wise cracks), but understand I'd need to commit to a heavyweight migration afterwards!
If the solution is to check for the existence of the original database using NSFileManager and delete/remove it if found, could someone please show the swift code with an example name of the original database, and how it can be effectively removed.
I've been trying several suggested solutions, such as dragging a copy of the .xcdatamodeld file onto the desktop, deleting the file in xcode and bringing it back in, but I keep getting the error that the model and store are not the same.
Answered in one line in first comment, but appreciated in reverse proportion.
I have an existing iPad application to which I've just added core data versioning. I've been through the documentation and followed the steps detailed. Now after choosing my new model as the current versioned model and trying to run it on my dev device from xCode I get the following error:
2012-03-28 07:35:42.137 DocsOnTap[2603:707] CoreData: error: (1) I/O error for database at /var/mobile/Applications/06EECF01-3598-4513-8A3A-BE4FD49EEBF6/Documents/.DocsOnTap.sqlite.migrationdestination_41b5a6b5c6e848c462a8480cd24caef3. SQLite error code:1, 'table Z_2TAG already exists'
The only change that I made to my model was to add in a single new entity. I have a table named Tag in my model - that appears to be what the error is referring to.
If I revert my current versioned model back to the previous model version then I can run my app on my dev device from Xcode without error.
I have read that there can be problems trying to use core data migration on dev devices. However I just want to test the process to be sure that when we update our app in the Appstore the migration works as expected for our customers.
In my case the same error appeared due to Renaming ID which was set in the Data Model inspector for the Entity. After I removed the Renaming ID the problem'd gone.
Well this was an obscure error. The entity that I was adding was named AppKeys - this must be the name of an entity used internally by core data or SQL Lite. I went back to scratch and found that I could add and migrate other attributes and entities without any problems. However if I tried once again to add my entity named AppKeys then I got the same error saying that 'table Z_2TAG already exists'. So the resolution to my problem is to choose another entity name. It is a pity that this is not documented somewhere obvious - or that the error was not more helpful. Anyway hopefully this might just help someone else one day.
I added new rows to my database through SQLiteManager but I cannot see those values in my tableview. My old values are seen. More interestingly, I deleted my database file but I can see my old values again in my tableview. When I created new database with new name, it sees that. How can I make it perceive new values?
Not directly an answer as there are at least two SQLite Managers.
SQLiteManager (standalone) and SQLite Manager the Firefox Plugin.
If you haven't tried the Firefox Plugin yet I'd strongly recommend doing so. I'm very happy with it and have never touched another SQLite Browser since.