In SQLite source code we can see a function named tabIsReadOnly with this comment: /* Return true if table pTab is read-only. So I think our friend user143482 is trying to acesse a "read only" table. So, it's seems hard to belive this can be a "chmod" problem, because if the file is read only, even creating table would be impossible as SQLite would be unable to write the "sqlite_master" data. In this db file we have of course the user tables but also the system tables so "sqlite_master" for example which contain the definiton of the tables. When I look at the data on the flash of the ESP I notice there is only one file for the whole db (there is also a temp file). I'm using SQLite on ESP32 and all answers here are "very strange". dbowner - The owner of the database to query dbname - The name of the database sql - The SQL query, base64 encoded Example. These can be generated in your Settings page, when logged in to DBHub.io. It worked apparently there just needed to be enough time for the resources to flush out to disk. Query parameters are passed via POST only, and all results are in a fairly verbose JSON format. If the create/drop failed, we waited for 50 ms and tried again, repeating until we succeeded or 5 seconds elapsed. We got around this by running a test write query against the db upon opening (e.g., creating then dropping a table with a silly name). We speculated that the problem was due to the fact that Windows (or the sqlite implementation under windows) doesn't always immediately clean up up file resources upon closing of a file. So if you want one user to be able to write, and another only to be able to read, you might try setting sharing permissions on the folder where the database resides. Consider a database on a CD SQLLite doesnt have the concept of users and permissions. dbfile fullfile(pwd,tutorial.db) conn sqlite(dbfile,readonly). Nothing wrong with a database you can only READ from. We eventually discovered that the threads that were failing were only those that were trying to open the database immediately after another thread had closed it (within 3 ms). For details, see Interact with Data in SQLite Database Using MATLAB Interface to. Our system was suffering this problem, and it definitely wasn't a permissions issue, since the program itself would be able to open the database as writable from many threads most of the time, but occasionally (only on Windows, not on OSX), a thread would get these errors even though all the other threads in the program were having no difficulties.
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