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--- built_in:database [2017/04/15 20:15]
65.103.182.121
+++ built_in:database [2017/04/15 20:23]
administrator old revision restored (2017/04/15 20:17)
@@ Line 1: / Line 1: @@
-snip tbh
+====== Database ======
+===== Description =====
+Create or open a database using the OpenDatabase method of the [[built_in:app|app]] object:
+<code>
+//the database is called "MyData"
+db = app.OpenDatabase( "MyData" );
+</code>
+To save your database in a specific folder, use an absolute path. See [[built_in:get_database_folder|GetDatabaseFolder]]
+===== Methods =====
+^Method ^Description ^
+|Database.Close() | |
+|Database.Delete() | |
+|Database.ExecuteSql( sql, params, success, error ) | |
+|Database.GetName() | |
+|Database.GetType() | |
+|Database.openError(e) | |
+|Database.openSuccess() | |
+===== Example =====
+//(sample taken from the DroidScript sample section)//
+<code javascript>
+//Called when application is started.
+function OnStart()
+{
+    //Create a layout with objects vertically centered.
+    lay = app.CreateLayout( "linear", "VCenter,FillXY" );
+    //Create an 'Add' button.
+    btnAdd = app.CreateButton( "Add to Database", 0.6, 0.1 );
+    btnAdd.SetOnTouch( btnAdd_OnTouch );
+    lay.AddChild( btnAdd );
+    //Create a 'Remove' button.
+    btnRemove = app.CreateButton( "Remove from Database", 0.6, 0.1 );
+    btnRemove.SetOnTouch( btnRemove_OnTouch );
+    lay.AddChild( btnRemove );
+    //Create a 'Delete' button.
+    btnDelete = app.CreateButton( "Delete Database", 0.6, 0.1 );
+    btnDelete.SetOnTouch( btnDelete_OnTouch );
+    lay.AddChild( btnDelete );
+    //Create text box to show results.
+    txt = app.CreateText( "", 0.9, 0.4, "multiline" );
+    txt.SetMargins( 0,0.1,0,0 );
+    txt.SetBackColor( "#ff222222" );
+    txt.SetTextSize( 18 );
+    lay.AddChild( txt );
+    //Add layout to app.
+    app.AddLayout( lay );
+    //Create or open a database called "MyData".
+    db = app.OpenDatabase( "MyData" );
+    //Create a table (if it does not exist already).
+    db.ExecuteSql( "CREATE TABLE IF NOT EXISTS test_table " +
+        "(id integer primary key, data text, data_num integer)" );
+    //Get all the table rows.
+    DisplayAllRows();
+}
+//Called when user touches our 'Add' button.
+function btnAdd_OnTouch()
+{
+    //Add some data (with error handler).
+    db.ExecuteSql( "INSERT INTO test_table (data, data_num)" +
+        " VALUES (?,?)", ["test", 100], null, OnError );
+    //Get all the table rows.
+    DisplayAllRows();
+}
+//Called when user touches our 'Remove' button.
+function btnRemove_OnTouch()
+{
+    //Remove data.
+    db.ExecuteSql( "DELETE FROM test_table WHERE id > 3" );
+    //Get all the table rows.
+    DisplayAllRows();
+}
+//Called when user touches our 'Delete' button.
+function btnDelete_OnTouch()
+{
+   //Delete this database.
+   db.Delete();
+   //Get all the table rows.
+   DisplayAllRows();
+}
+//function to display all records
+function DisplayAllRows()
+{
+    txt.SetText("");
+    //Get all the table rows.
+    db.ExecuteSql( "select * from test_table;", [], OnResult );
+}
+//Callback to show query results in debug.
+function OnResult( results )
+{
+    var s = "";
+    var len = results.rows.length;
+    for(var i = 0; i < len; i++ )
+    {
+        var item = results.rows.item(i)
+        s += item.id + ", " + item.data + ", " + item.data_num + "\n";
+    }
+    txt.SetText( s );
+}
+//Callback to show errors.
+function OnError( msg )
+{
+    app.Alert( "Error: " + msg );
+    console.log( "Error: " + msg );
+}
+</code>

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