In short, the application connects to the database (SQLite) and reads information from it.

The problem is that everything works as it should on the emulator, the application is fully functional. But when you run the application on the device, it crashes.

Why does everything work as it should on the emulator, but does a crash occur on the device?

The application crashes on these lines of code:

  1. either here:

    mDatabaseHelper = new DataBaseHelper(this, "mydatabase.db", null, 1); mSqLiteDatabase = mDatabaseHelper.getWritableDatabase();

  2. or, if instead of those lines use mSqLiteDatabase = this.openOrCreateDatabase("mydatabase.db", MODE_PRIVATE, null) , here:

     Cursor cursor = mSqLiteDatabase.query(DataBaseHelper.DATABASE_TABLE, new String[]{ DataBaseHelper.NAME, DataBaseHelper.NUMBER}, null,null,null,null,null);

Identified by experience.

StackTrace with the second option (the creation of the cursor takes place on the 30th line in StartActivity ):

  Process: ru.startandroid.begin, PID: 12643 java.lang.RuntimeException: Unable to start activity ComponentInfo{ru.startandroid.begin/ru.startandroid.begin.StartActivity}: android.database.sqlite.SQLiteException: no such table: database1 (code 1): , while compiling: SELECT name, number FROM database1 ################################################################# Error Code : 1 (SQLITE_ERROR) Caused By : SQL(query) error or missing database. (no such table: database1 (code 1): , while compiling: SELECT name, number FROM database1) ################################################################# at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3184) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3294) at android.app.ActivityThread.access$1000(ActivityThread.java:210) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1704) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:145) at android.app.ActivityThread.main(ActivityThread.java:6938) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199) Caused by: android.database.sqlite.SQLiteException: no such table: database1 (code 1): , while compiling: SELECT name, number FROM database1 ################################################################# Error Code : 1 (SQLITE_ERROR) Caused By : SQL(query) error or missing database. (no such table: database1 (code 1): , while compiling: SELECT name, number FROM database1) ################################################################# at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method) at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1093) at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:670) at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588) at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:59) at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37) at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44) at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1454) at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1301) at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1172) at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1340) at ru.startandroid.begin.StartActivity.onCreate(StartActivity.java:30) at android.app.Activity.performCreate(Activity.java:6575) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1134) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3137) ... 10 more

Complete database creation

 package ru.startandroid.begin; import android.content.Context; import android.database.DatabaseErrorHandler; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; public class DataBaseHelper extends SQLiteOpenHelper { // имя базы данных private static final String DATABASE_NAME = "mydatabase.db"; // версия базы данных private static final int DATABASE_VERSION = 1; //имя таблицы public static final String DATABASE_TABLE = "database1"; // название столбцов public static final String NAME = "name"; public static final String NUMBER = "number"; //скрипт создания private static final String SCRIPT = "CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + " (" + " integer primary key autoincrement, " + NAME + " text no null, " + NUMBER + " long, " + " (Field1 VARCHAR, Field2 VARCHAR;)"; DataBaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } ////конструктор БД public DataBaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) { super(context, name, factory, version); } public DataBaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version, DatabaseErrorHandler errorHandler) { super(context, name, factory, version, errorHandler); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(SCRIPT); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // Удаляем старую таблицу и создаём новую db.execSQL("DROP TABLE IF IT EXISTS " + DATABASE_TABLE); // Создаём новую таблицу onCreate(db); } }

and full Cursor code

 package ru.startandroid.begin; import android.app.ListFragment; import android.app.ListActivity; import android.content.Intent; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.util.StringBuilderPrinter; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView; public class StartActivity extends ListActivity { private ArrayAdapter<String> mAdapter; private DataBaseHelper mDatabaseHelper; private SQLiteDatabase mSqLiteDatabase; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); //подключаемся к БД!!!!! //mDatabaseHelper = new DataBaseHelper(this, "mydatabase.db", null, 1); //mSqLiteDatabase = mDatabaseHelper.getWritableDatabase(); mSqLiteDatabase = this.openOrCreateDatabase("mydatabase.db", MODE_PRIVATE, null); ///////////////////////////////////// List Cursor cursor = mSqLiteDatabase.query(DataBaseHelper.DATABASE_TABLE, new String[] { DataBaseHelper.NAME, DataBaseHelper.NUMBER}, null,null,null,null,null); //cursor.moveToFirst(); } }
  • five
    Immediately we can assume about 48 reasons. Unfortunately, they all do not fit into the comment and you need to attach the stackTrace error and the exact line of its occurrence to shorten the list of possible causes - Juriy Spb ♦
  • Edited the question - Dmitry
  • It seems that you do not create a database / table in it. Those. you access the database / table before you create / fill it with data. Show how you create the table and where you call this method. - Yuriy SPb ♦
  • Data added - Dmitry
  • one
    No, filling in the creation does not help. Well, thank you very much for your help. Probably the best solution at this stage, it's just to write everything all over again, because there is almost nothing in the project anyway, and I found working options, I will be guided by them) - Dmitry

3 answers 3

In line:

 private static final String SCRIPT = "CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + " (" + " integer primary key autoincrement, " + NAME + " text no null, " + NUMBER + " long, " + " (Field1 VARCHAR, Field2 VARCHAR;)";

missing column name with id.

UPD Thanks to the more attentive Andrey Mihalev in the next answer, we end up with the following line:

 private static final String SCRIPT = "CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + " (" + "_id integer primary key autoincrement, " + NAME + " text not null, " + NUMBER + " integer, " + " Field1 VARCHAR, Field2 VARCHAR)";

    You have errors when creating a database. Here he also swears that there is no necessary table. On the emulator, most likely the database has already been created earlier, and there are no problems in it, problems will occur when you change the DATABASE_VERSION variable for example to 2. your code:

     private static final String SCRIPT = "CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + " (" + " integer primary key autoincrement, " + NAME + " text no null, " + NUMBER + " long, " + " (Field1 VARCHAR, Field2 VARCHAR;)";

    ID is missing in "integer primary key autoincrement,"

     "_id integer primary key autoincrement, "

    in sql there is no word no, there is a word not therefore the text "text no null," is fixed to

     " text not null, "

    the last fields for some reason are placed in brackets "(Field1 VARCHAR, Field2 VARCHAR;)" the first bracket is simply not needed! and remove the semicolon at the end.

     " Field1 VARCHAR, Field2 VARCHAR)"

    total it turns out that your variable SCRIPT will look like this:

     private static final String SCRIPT = "CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + " (" + "_id integer primary key autoincrement, " + NAME + " text not null, " + NUMBER + " integer, " + " Field1 VARCHAR, Field2 VARCHAR)";
    • yes, I also noticed later about "no null", I didn’t even think that there could be so many errors on one line :( - but you already wrote the answer. Another long one needs to be replaced by INTEGER - there is no long type in SQLite - pavlofff
    • really looked long. I have no rights to leave comments to other answers, so I had to leave mine. - Andrey Mihalev
    • But you have the full right to publish the answer and get a well-deserved reputation for attentiveness :) - pavlofff

    But in my opinion everything is much simpler.

    Rename the fields - name and number - at least not quite good names for the fields. In addition, in Android the rule is the name of the primary key _ID - too lazy to look for a link.

    • _id (and not _ID) is not the rule, but the harsh necessity of naming the primary key, if Android standard classes are used to work with the database, like Cursor , and there is a desire for them to work - pavlofff
    • In the BaseConstants class, BaseConstants is a BaseConstants constant that contains the string _id - Flippy