The SetCallback function stores the address of our Xojo function for later use. We pass it the address of a Xojo function in which we'll handle the installation of our custom functions. This is a function we'll call from Xojo before loading this extension into the sqlite engine. The first relevant part here is the SetCallback function. so files of the ICU-sqlite lib on the web and use them with these instructions. I believe, however, that you can more easily find. Mind you, only for OS X, though, as I do not have the time to make and test versions for Windows and Linux as well. Therefore, I'm making my own built version available, along with the source code. And unfortunately, there is none publically available as far as I could see, at least not for OS X. Still, you need to have a readily built ICU lib for sqlite before you can load it. Furtunately, though, Xojo's plugin allows dynamic loading of extensions (like plugins) into the sqlite engine. This is not a viable option with Xojo because you'd also have to write your own Database plugin to make the sqlite lib usable in Xojo (while the sqlite lib is open source, Xojo's plugin is not, or this would be less of an issue). The usual solution to this is to compile the sqlite3 library with ICU support and then include this lib in your program. This missing unicode support also affects sorting and related comparison functions. only the plain ASCII chars (a-z) will get uppercased but not the special french chars. For instance, if you try to use the SQL function upper on a french phrase such as Tête-à-Tête, you will get TêTE-à-TêTE, i.e. PostgreSQL and MySQL are popular alternatives.Xojo's default Database class REALSQLDatabase (or its replacement SQLiteDatabase), which is based on sqlite, does not support international (non-english) characters. Your final option is to switch to an actual database server. CubeSQL and Valentina have products available that can do this. If you want to stick with SQLite but would rather not create a web service, another option to consider is to use a product that puts a database server around SQLite. To learn more about database web services, check out the Making Database Web Services video.īy the way, this is also why a regular web app can safely use SQLite with multiple users - the web app manages the multiple users but is the only app that is connected to the SQLite database. The Eddie’s Electronics Web Service sample shows you how you might set this up: Examples/Communication/Web Services/EddiesWebServiceĪnother option for setting up your own database web service is to use the Aloe open-source project, which gives you a robust framework for building web services. This works because the web app is the only app that is connected to the SQLite database. The web app can accept requests from multiple client apps (or any type - desktop, web, mobile, etc.), fetch the data requested from the SQLite database and then send it back as JSON. The most obvious solution is to create a web service by using a web app with WebApplication.HandleURL (or HandleSpecialURL). If you want to stick with SQLite then you’ll need to put something in front of it that can handle requests from multiple client apps. So what are your options when you want to share your database? Because this problem results from bugs in the underlying filesystem implementation, there is nothing SQLite can do to prevent it.Ī good rule of thumb is to avoid using SQLite in situations where the same database will be accessed directly (without an intervening application server) and simultaneously from many computers over a network. If file locking does not work correctly, two or more clients might try to modify the same part of the same database at the same time, resulting in corruption. Also, file locking logic is buggy in many network filesystem implementations (on both Unix and Windows). SQLite will work over a network filesystem, but because of the latency associated with most network filesystems, performance will not be great. If there are many client programs sending SQL to the same database over a network, then use a client/server database engine instead of SQLite. Situations Where A Client/Server RDBMS May Work Better I’ll quote the relevant section from their “ When to use SQLite” page: This is a really bad idea, as even the SQLite folks will tell you. Essentially they want to know how to use SQLite as a server and the most common questions relate to putting a SQLite database file on a shared network drive and accessing the database file from apps running on multiple computers. People often ask about a way to share a SQLite database across multiple apps.
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