Question

I have a db that is structred as such

uid | username | password |     email   | cur_level
1     default      abc123   [e-mail]    0

In my game after you complete a level in the main activity I run a method called increase_current_level()
value++;
test_db.open();
test_db.updateLevel(value);
cur_level = value;
test_db.close();

So that seems to work with no problems but when test_db.updateLevel(value) is run, that when the program crashes.

In my DBHelper the code for update level is as follows.

public boolean updateLevel(String level) {
        ContentValues args = new ContentValues();

        args.put(KEY_CUR_LEVEL, level);
        return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "="
                + "WHERE id=(SELECT max(id) FROM DATABASE_TABLE)", null) > 0;

    }

My log cat error seems to be:

10-17 17:36:10.833: E/AndroidRuntime(1815): Caused by: android.database.sqlite.SQLiteException: near "WHERE": syntax error (code 1): , while compiling: UPDATE test SET cur_level=? WHERE _id=WHERE id=(SELECT max(id) FROM DATABASE_TABLE)

I’m very new to SQLite so, it’s kind of intimidating, but I hope someone sees a very obvious flaw. Thanks

Update 1:

My updated code:

public boolean updateLevel(String level) {
    ContentValues args = new ContentValues();

    args.put(KEY_CUR_LEVEL, level);
    return mDb.update(DATABASE_TABLE, args, KEY_ROWID + " = (SELECT max(id) FROM DATABASE_TABLE",
            null) > 0;

}

Updated error msg:

10-17 18:26:50.804: E/AndroidRuntime(3684): Caused by: android.database.sqlite.SQLiteException: near "DATABASE_TABLE": syntax error (code 1): , while compiling: UPDATE test SET cur_level=? WHERE _id = (SELECT max(id) FROM DATABASE_TABLE

Answer 1

The syntax of mDb.update is

update(table, ContentValues values, String whereClause, String[] whereArgs)

Let’s assume that KEY_ROWID = "id"

For your whereClause, you’re literally passing

"id = WHERE id = (SELECT max(id) FROM DATABASE_TABLE"

which is not valid SQL.

You don’t seem to need “id =“. Just start your WHERE clause with “WHERE id=“

However, your question implies that you have only one record in the DB. Why use a DB for one record? And if you have more than one record in it, you should use a WHERE clause that searches on something unique, rather than using SELECT max(id).

The bottom line is that you need to improve your knowledge of SQL.