Sqlite: check if database exist

Question

I am developing a mobile application using phonegap that store some data into the local database (sqlite DB). I need to know if the database exist or not, and that to determ

Answer 1

I needed to do something similar, I needed to check if the application had a db already created (legacy DB) and if so export all the data to the new db (new and improved DB) and then delete this DB.

Background Info: I was moving from simple keyvalue tables to complex relational DB with cascades etc.

function onDeviceReady() {
    // CHECK IF LEGACY DATABASE EXISTS. IF DOES EXPORT EXISTING DATA TO NEW DB THEN DELETE LEGACY
    window.resolveLocalFileSystemURL(cordova.file.applicationStorageDirectory + "/databases/.db", exportToNewDB, setupDB);
}

Note: If file exists (success), then we need to do our export code in here, then delete file so this method will always fail. If file doesn't exist - user has already exported to new DB or they our new user and never had legacy DB.

// Fail Method
function setupDB() {
    newDB = window.sqlitePlugin.openDatabase({ name: ".db" });
    newDB.transaction(sql.initDB, sql.errorCallback, sql.successCallBack);
}
// Success Method
function exportToNewDB() {
    db = window.sqlitePlugin.openDatabase({ name: ".db" });
    db.transaction(function (tx) {
         setupDB();
         // Insert Export code Here

         // Delete DB
         window.sqlitePlugin.deleteDatabase(".db", sqlSuccess, sqlFail);
    }, sqlFail);
}

Answer to your Question:

window.resolveLocalFileSystemURL(cordova.file.applicationStorageDirectory + "/databases/my_db.db", process_1, process_2);