Java String concatenation with BaseColumns._ID brings an error <p>In eclipse as soon as i type this out:</p> <pre><code>BaseColumns._ID, + "=?" </code></pre> <p>I get:</p> <pre><code>The operator + is undefined for the argument type(s) String </code></pre> <p>How is that possible, they are both Strings aren't they?</p> <p>now here is documentation for BaseColumns._ID:</p> <pre><code>public static final String _ID </code></pre> <p>the code I am writing is:</p> <pre><code>public void deteleProfile(Long id) throws SQLException { SQLiteDatabase db = helper.getWritableDatabase(); Integer i = db.delete(ProlificDatabase.TABLE, BaseColumns._ID, + "=?", new String[] {id.toString()}); Log.d(TAG, i + " records deleted where id is " + id); </code></pre>