It is characterized as ‘self-describing’ and easy to understand. It is a lightweight format intended to transport and store data. It has no relation with JavaScript the similarity in the name comes from the fact that JSON also stores its data in the form of an object the same way JavaScript does. JSON stands for JavaScript Object Notation. In SQLite, JSON functions, as well as operators, are built by default. It is compatible with all programming languages, easy to read and write, and for software to parse. JSON is a text-based way of representing JavaScript arrays, object literals, and scaler data. The JSON file produced contains the following data.Robert Seethalers Roman „Der Trafikant“ – schneller Überblick anhand von Schaubildern Path.Combine(exportPath, exportBackupJson), true) Ĭonsole.WriteLine("There is no data to export.") Ĭonsole.WriteLine("Data export successful.") Ĭonsole.WriteLine("Data export unsuccessful.") Path.Combine(exportPath, exportBackupJson)).Date !=įile.Copy(Path.Combine(exportPath, exportJson), (File.Exists(Path.Combine(exportPath, exportBackupJson)) & if (!File.Exists(Path.Combine(exportPath, exportBackupJson)) || Check if the backup file does not exist, or if it does, check that // today's date is different from the last modified date. string exportBackupJson = exportJson.Substring(0, exportJson.Length - 5) + JsonString = JsonConvert.SerializeObject(collectionWrapper, If data has been returned, do the export. Execute SQL and place data in a reader object. SqlSelect.CommandText = id, firstname, lastname, title, dob Query text incorporated into SQL command. Display a message stating file path does not exist.Ĭonsole.WriteLine("File path does not exist.") string exportPath = exportJson = "personexport.json" Message confirming unsuccessful database connection.Ĭonsole.WriteLine("Database connection unsuccessful.") Message confirming incorrect database location.Ĭonsole.WriteLine("Error locating database.") Ĭonnect = new SqliteConnection("Data Source=" + database + " " + Once added, a ‘ using‘ statement for the ‘Newtonsoft.Json’ namespace needs to be included, along with 'System.Data'. Before running this command it is necessary to navigate to the folder where the project resides. The following command can be used to install the above mentioned package. For IDEs that don't have a built in package manager, PowerShell can be used. Visual Studio incorporates NuGet Package Manager, which allows for packages to be searched for and installed. This can be done in a couple of different ways, depending on what Integrated Development Environment (IDE) is being used. It should be noted that in order for this to work, the package 'Newtonsoft.Json' needs to be added to the project. Backups are then overwritten each week.įeedback is provided as to the success or failure of the task. Note that the backup is only done for the first time that this is run in a given day. Here, Sunday is classed as the first day of the week, with an index value of zero. This makes a copy of the JSON file that has just been created, giving it a name that includes the index number for the day of the week, along with the day itself, for example, 'personexport-1-monday.json', for the backup on a Monday. The contents of the file is then constructed.Ī rolling seven day backup is also included. If data is returned, the JSON file is opened for writing. The data is then extracted from the database and assigned to a 'reader' object. If it does, a connection to the database is established, the path to the resulting JSON file is set, along with its name and a check is made to see if the path is valid. JSON or JavaScript Object Notation files are an alternative file format to CSV, that can sometimes be used for both of these scenarios.īelow is an example of how C# can be used to export data to a JSON file called ‘personexport.json’, from an SQLite database table called ‘person’, which was used in the examples for selecting, inserting, updating, deleting, importing ( CSV, text, XML and JSON) and exporting data ( CSV, text and XML).įirstly, a check is made to see if the database file actually exists. Sometimes it can be useful to export data from a database, so that it can be analysed, or, to import in to another computer system.
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