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<column definition name> or <table constraint> expected, got 'Index'

I have got the error message " or expected, got 'Index'" when I was trying to create a table and I do not really understand why is the code expecting a column definition or table constraint at this line
I have tried with changing the whitespaces, however that only change the place where the error is prompted. The content of the error message does not change
This is the part that I have declared the strings
public class TaskEntry implements BaseColumns {
public static final String TABLE = "Users";
public static final String INDEX = "Index";
public static final String COL_TASK_TITLE = "title";
}
The following is my code for the creating table part
public void onCreate(SQLiteDatabase db) {
String createTable = "CREATE TABLE " + Item_contract.TaskEntry.TABLE + " ( " +
Item_contract.TaskEntry._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
Item_contract.TaskEntry.INDEX + " INTEGER NOT NULL, " +
Item_contract.TaskEntry.COL_TASK_TITLE + " TEXT NOT NULL" + ");";
db.execSQL(createTable);
}

You cannot use INDEX as a column name as it is a keyword.
The SQL standard specifies a large number of keywords which may not be
used as the names of tables, indices, columns, databases, user-defined
functions, collations, virtual table modules, or any other named
object. The list of keywords is so long that few people can remember
them all. For most SQL code, your safest bet is to never use any
English language word as the name of a user-defined object.
SQL As Understood By SQLite - SQLite Keywords
So change
public static final String INDEX = "Index";
perhaps to
public static final String INDEX = "IX";
You could enclose the column name if you really wanted it to be INDEX e.g.
public static final String INDEX = "[Index]";
As per :-
If you want to use a keyword as a name, you need to quote it. There are four ways of quoting keywords in SQLite:
'keyword' A keyword in single quotes is a string literal.
"keyword" A keyword in double-quotes is an identifier.
[keyword] A keyword enclosed in square brackets is an identifier. This is not standard SQL. This quoting mechanism is used by MS Access and SQL Server and is included in SQLite for compatibility.
`keyword` A keyword enclosed in grave accents (ASCII code 96) is an identifier. This is not standard SQL. This quoting mechanism is used by MySQL and is included in SQLite for compatibility.
SQL As Understood By SQLite - SQLite Keywords
Note
You will have to do one of the following to get the onCreate method to run and thus alter the schema:-
Delete the App's data.
Uninstall the App.

Obtaining table names for sqlite SQL join in android

I have a need to join standard android's tables (like contacts and call log) using SQL. It is possible using the rawQuery or query methods of SQLiteDatabase class. But for the methods to work properly I need to know table names that I can provide in a raw SQL query.
Example. I want to execute query like this:
SELECT * FROM Contacts as c INNER JOIN Call_Log as l ON c.number=l.number
I know how to get field names (like CallLog.Calls.NUMBER), but I don't know how to get the name of a standard table that every android has. It is possible to hardcode the name, but the way with something like CallLog.TABLE_NAME looks much more reliable. So, where can I find an analogue of CallLog.TABLE_NAME?

Your asking for a lot of info, but this is a good summation of how to access the contacts table and how to create your own SQL table and update it with information you get from other tables.
To do any type of search of the Contacts Provider, your app must have READ_CONTACTS permission. To request this, add this element to your manifest file as a child element of :
<uses-permission android:name="android.permission.READ_CONTACTS" />
To do any type of search of the Call Log, your app must have READ_CALL_LOG permission. To request this, add this element to your manifest file as a child element of :
<uses-permission android:name="android.permission.READ_CALL_LOG" />
Code below on how to access Phone Call History
Uri allCalls = Uri.parse("content://call_log/calls");
Cursor c = managedQuery(allCalls, null, null, null, null);
String num= c.getString(c.getColumnIndex(CallLog.Calls.NUMBER));// for number
String name= c.getString(c.getColumnIndex(CallLog.Calls.CACHED_NAME));// for name
String duration = c.getString(c.getColumnIndex(CallLog.Calls.DURATION));// for duration
int type = Integer.parseInt(c.getString(c.getColumnIndex(CallLog.Calls.TYPE)));// for call type, Incoming or out going.
This technique tries to match a search string to the name of a contact or contacts in the Contact Provider's ContactsContract.Contacts table. You usually want to display the results in a ListView, to allow the user to choose among the matched contacts.
Saving data to a database is ideal for repeating or structured data, such as contact information. This class assumes that you are familiar with SQL databases in general and helps you get started with SQLite databases on Android. The APIs you'll need to use a database on Android are available in the android.database.sqlite package.
One of the main principles of SQL databases is the schema: a formal declaration of how the database is organized. The schema is reflected in the SQL statements that you use to create your database. You may find it helpful to create a companion class, known as a contract class, which explicitly specifies the layout of your schema in a systematic and self-documenting way.
A contract class is a container for constants that define names for URIs, tables, and columns. The contract class allows you to use the same constants across all the other classes in the same package. This lets you change a column name in one place and have it propagate throughout your code.
A good way to organize a contract class is to put definitions that are global to your whole database in the root level of the class. Then create an inner class for each table that enumerates its columns.
public final class FeedReaderContract {
// To prevent someone from accidentally instantiating the contract class,
// make the constructor private.
private FeedReaderContract() {}
/* Inner class that defines the table contents */
public static class FeedEntry implements BaseColumns {
public static final String TABLE_NAME = "entry";
public static final String COLUMN_NAME_TITLE = "title";
public static final String COLUMN_NAME_SUBTITLE = "subtitle";
}
}
Once you have defined how your database looks, you should implement methods that create and maintain the database and tables. Here are some typical statements that create and delete a table:
private static final String TEXT_TYPE = " TEXT";
private static final String COMMA_SEP = ",";
private static final String SQL_CREATE_ENTRIES =
"CREATE TABLE " + FeedEntry.TABLE_NAME + " (" +
FeedEntry._ID + " INTEGER PRIMARY KEY," +
FeedEntry.COLUMN_NAME_TITLE + TEXT_TYPE + COMMA_SEP +
FeedEntry.COLUMN_NAME_SUBTITLE + TEXT_TYPE + " )";
private static final String SQL_DELETE_ENTRIES =
"DROP TABLE IF EXISTS " + FeedEntry.TABLE_NAME;
Just like files that you save on the device's internal storage, Android stores your database in private disk space that's associated application. Your data is secure, because by default this area is not accessible to other applications.
A useful set of APIs is available in the SQLiteOpenHelper class. When you use this class to obtain references to your database, the system performs the potentially long-running operations of creating and updating the database only when needed and not during app startup. All you need to do is call getWritableDatabase() or getReadableDatabase().
To use SQLiteOpenHelper, create a subclass that overrides the onCreate(), onUpgrade() and onOpen() callback methods. You may also want to implement onDowngrade(), but it's not required.
For example, here's an implementation of SQLiteOpenHelper that uses some of the commands shown above:
public class FeedReaderDbHelper extends SQLiteOpenHelper {
// If you change the database schema, you must increment the database version.
public static final int DATABASE_VERSION = 1;
public static final String DATABASE_NAME = "FeedReader.db";
public FeedReaderDbHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public void onCreate(SQLiteDatabase db) {
db.execSQL(SQL_CREATE_ENTRIES);
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// This database is only a cache for online data, so its upgrade policy is
// to simply to discard the data and start over
db.execSQL(SQL_DELETE_ENTRIES);
onCreate(db);
}
public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
onUpgrade(db, oldVersion, newVersion);
}
}
To access your database, instantiate your subclass of SQLiteOpenHelper:
FeedReaderDbHelper mDbHelper = new FeedReaderDbHelper(getContext());
Put Information into a Database
Insert data into the database by passing a ContentValues object to the insert() method:
// Gets the data repository in write mode
SQLiteDatabase db = mDbHelper.getWritableDatabase();
// Create a new map of values, where column names are the keys
ContentValues values = new ContentValues();
values.put(FeedEntry.COLUMN_NAME_TITLE, title);
values.put(FeedEntry.COLUMN_NAME_SUBTITLE, subtitle);
// Insert the new row, returning the primary key value of the new row
long newRowId = db.insert(FeedEntry.TABLE_NAME, null, values);
The first argument for insert() is simply the table name.
The second argument tells the framework what to do in the event that the ContentValues is empty (i.e., you did not put any values). If you specify the name of a column, the framework inserts a row and sets the value of that column to null. If you specify null, like in this code sample, the framework does not insert a row when there are no values.
To read from a database, use the query() method, passing it your selection criteria and desired columns. The method combines elements of insert() and update(), except the column list defines the data you want to fetch, rather than the data to insert. The results of the query are returned to you in a Cursor object.
SQLiteDatabase db = mDbHelper.getReadableDatabase();
// Define a projection that specifies which columns from the database
// you will actually use after this query.
String[] projection = {
FeedEntry._ID,
FeedEntry.COLUMN_NAME_TITLE,
FeedEntry.COLUMN_NAME_SUBTITLE
};
// Filter results WHERE "title" = 'My Title'
String selection = FeedEntry.COLUMN_NAME_TITLE + " = ?";
String[] selectionArgs = { "My Title" };
// How you want the results sorted in the resulting Cursor
String sortOrder =
FeedEntry.COLUMN_NAME_SUBTITLE + " DESC";
Cursor c = db.query(
FeedEntry.TABLE_NAME, // The table to query
projection, // The columns to return
selection, // The columns for the WHERE clause
selectionArgs, // The values for the WHERE clause
null, // don't group the rows
null, // don't filter by row groups
sortOrder // The sort order
);
To look at a row in the cursor, use one of the Cursor move methods, which you must always call before you begin reading values. Generally, you should start by calling moveToFirst(), which places the "read position" on the first entry in the results. For each row, you can read a column's value by calling one of the Cursor get methods, such as getString() or getLong(). For each of the get methods, you must pass the index position of the column you desire, which you can get by calling getColumnIndex() or getColumnIndexOrThrow(). For example:
cursor.moveToFirst();
long itemId = cursor.getLong(
cursor.getColumnIndexOrThrow(FeedEntry._ID)
);

Android SqLite no such column _id exception

Don't immediately flag me for a duplicate question. My issue is different because I have a correctly formatted SQL query.
public static final String TABLE_NAME = "log";
public static final String COLUMN_ID = "_id";
public static final String LOG_TEXT = "logtext";
private static final String TABLE_CREATE = "CREATE TABLE " + TABLE_NAME + " (" +
COLUMN_ID + " integer primary key autoincrement, " +
LOG_TEXT + " TEXT not null);";
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(TABLE_CREATE);
}
and I query here
String[] columns = {LOG_TEXT,COLUMN_ID};
Cursor cursor = helper.getReadableDatabase().query(TABLE_NAME, columns, null, null, null, null, COLUMN_ID + " desc");
and I catch this the exception generated containing the sql query.
catch(Exception e){
Log.D("sql Exception",e.getMessage());}
and it returns
no such column: _id: , while compiling: SELECT logtext, _id FROM log ORDER BY _id desc
I'm familar with Oracle SQL and relational databases in general. Is it my ORDER BY clause? I was certain you can ALWAYS use order by. It doesn't have the same behavior as GROUP BY.
Any ideas on why the exception?
Incase anyone wants to see i'm updating with my ArrayAdaptor statements. I'm using the cursor in a listview
String[] data = query();
adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, data);
listView.setAdapter(adapter);}

Rewrite
Whenever you change the schema in TABLE_CREATE you must inform you app of these changes, they will not happen automatically when you change TABLE_CREATE. The easiest way to do this is to increment your database_version in your extended SQLiteOpenHelper class. You discovered you can also uninstall / reinstall the app, for the same results. If you are savvy with SQL you could ALTER the table. But whatever the method you must make sure that you app makes the schema changes before trying to access the new columns...
Also for SQLite:
_id integer primary key
is synonymous with:
_id integer primary key autoincrement not null
And queries use descending as the default order, so ORDER BY _id is the same as ORDER BY _id DESC.

Had the same problem, meaning it should have worked but didn't (had some typos in the create command that I fixed but that still didn't help). A colleague then told me to try clearing the data (just at AppInfo and then "Clear Data") which solved my problem, apparently the old database (that didn't work) was still there and had to be cleared out first.
I just put this answer here in case anybody else like me (android beginner) stumbles across this problem, because I went through dozens of stackoverflow threads with this problem but not one offered this possibility/solution and it bothered me for quite some time.

Did you add the definition of the _id column to your create statement later on, i.e. after the code had already been run once? Databases are persisted files, so if you modify the table structure in your code you need to make sure you clear your application's data so the database file can ge re-created with the correct table/column data.

Simple Joined Table in SQLite on Android

I'm trying to do something simple here but my knowledge on databases and SQL is rusty at best.
I'm was following a tutorial here and am now trying to make my own joined table.
To explain a bit more simply, Profiles have widgets, widgets can be of multiple types.
The widget table contains an id, a name and a string widget_type. For each widget type, there will be another table for that widget_type.
So
Profile
|
|
|
Widget
|
|------------------|--------------------|
Widget1 Widget2 Widget3
The part I'm having trouble with is sharing the Id's among the widgets so that they are unique across all 3 widget tables. Heres the SQL I have below but I'm not entirely sure what I'm trying to do is called or if it can be done from within SQLite
private static final String PROFILE_DATABASE_CREATE = "create table "
+ TABLE_PROFILES + "( " + COLUMN_ID
+ " integer primary key autoincrement, " + PROFILE_COLUMN_NAME
+ " text not null);";
// Widget creation SQL statement
private static final String WIDGET_DATABASE_CREATE = "create table "
+ TABLE_WIDGETS + "(" + COLUMN_ID +"integer primary key autoincrement" + WIDGET_COLUMN_TYPE +"text not null";

Urk. Hard to do this so that the IDs in Widget1 are different from the IDs in Widget2.
A more simple way is to collapse all the tables together. The Contacts Provider that backs the People application does this. Have one table containing the data for all three widget types. Differentiate a row for a particular widget type with a unique MIME type. Add a widget by adding it to the table with the _ID value of the profile it belongs to, the MIME type for its widget type, and its data.
The trick is to give this "generic widget" table the maximum number of columns you'd need for any type of widget. Provide some columns that are the same for any widget, and then some generic columns (say DATA1 through DATA5) whose contents vary according to the type of widget. Then assign type-specific constants for each widget type
For example, for the Widget table you'd create these column name constants
private static final String _ID = "_ID";
private static final String WIDGET_NAME = "name";
private static final String WIDGET_TYPE = "MIMEtype";
then
private static final String WIDGET1_TYPE = "vnd.example.com/widget1";
private static final String WIDGET2_TYPE = "vnd.example.com/widget2";
private static final String WIDGET3_TYPE = "vnd.example.com/widget3";
and
private static final String SOME_WIDGET1_COLUMN = "DATA1";
private static final String SOME_OTHER_WIDGET2_COLUMN = "DATA2";
etc.
It really doesn't matter if you retrieve a row of MIME type "vnd.example.com/widget1" and then access the cursor using "SOME_OTHER_WIDGET2_COLUMN", but it's easier to keep track of what's going on if you use the Widget1 constants on Widget1 cursors, etc.
If you've ever wondered what all the contract classes for android.provider do, well, this is it.

why does db.insert() giving the sqliteconstraintexception error 19 constraint failed

I have read most of the questions related to this exception but none of them are clear or indicative of why db.insert would throw this error. It was working fine without errors until I manually deleted the db from DDMS. Following is my SQLiteOpenHelper code:
public class LoginSQLiteOpenHelper extends SQLiteOpenHelper {
public static final String DB_NAME = "logincredentials.sqlite";
public static final int DB_VERSION_NUMBER = 1;
public static final String DB_TABLE_NAME = "credentials";
public static final String USERNAME = "user_name";
public static final String PASSWORD = "password";
private static final String DB_CREATE_SCRIPT = "create table " + DB_TABLE_NAME +
"( _id integer primary key autoincrement," +
USERNAME + " text not null, " +
PASSWORD + " text not null );" ;
public LoginSQLiteOpenHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION_NUMBER);
}
#Override
public void onCreate(SQLiteDatabase aSqliteDB) {
Logger.d("Create", "Creating the database...");
aSqliteDB.execSQL(DB_CREATE_SCRIPT);
}
}
My code for inserting the values is:
ContentValues contentValues = new ContentValues();
contentValues.put(LoginSQLiteOpenHelper.USERNAME, loginId);
contentValues.put(LoginSQLiteOpenHelper.PASSWORD, password);
database.insert(LoginSQLiteOpenHelper.DB_TABLE_NAME, null, contentValues);

This is why it occurred to me. If you declare one of your column name type as UNIQUE in your Create Table query in Database and try to insert a non unique variable, it invokes SQLiteConstraintException error.
A UNIQUE constraint is similar to a PRIMARY KEY constraint, except that a single table may have any number of UNIQUE constraints. For each UNIQUE constraint on the table, each row must feature a unique combination of values in the columns identified by the UNIQUE constraint. As with PRIMARY KEY constraints, for the purposes of UNIQUE constraints NULL values are considered distinct from all other values (including other NULLs). If an INSERT or UPDATE statement attempts to modify the table content so that two or more rows feature identical values in a set of columns that are subject to a UNIQUE constraint, it is a constraint violation. Source - http://www.sqlite.org/lang_createtable.html

I have read pretty much all forums looking for an exact reason for the occurrence of this exception. However, nowhere it clearly states so. However, by means of this code of mine, I can explain why it ocurred for me.
The code snippet I provided, is actually flawless. I am doing exactly what is required to do a db.insert().
However, i figured out the exception in 2 steps.
1. first time when i inserted values, I did not insert a value for the column Password.
2. second time, I added a value for column for Password, but due to incorrect passing of values it was null.
hence, I deduced from this exercise, that no column are allowed null values. You must initialize them with some value.
Please feel free to comment/add or correct me if I am wrong. I would like anyone else running into this issue to be clear on it as there are no good documentation on this exception.