I'm trying to insert values on Android SQLite Database. The question is, I'm trying to insert a word, the table has 3 columns, ID, WORD, COUNT.
When I insert a word in the database, some method will verify if this word exists on the database. If yes, it will increment the value of COUNT for this word.
Example. I have a word "Question" in the database with COUNT value 1, and i want to insert it again, the method will find this word and if I want to insert "qUeSTion" it doesnt matter, it will return "Question" for me when I retrieve the data, and it will increment the value of COUNT from 1 to 2. Got it??
SO here is my code. I'm having problems when try to do this, this verification. I dont know what method to use, etc. I'm using SQLiteStatement for insert. But the methods which offers doesn work. Any Idea of what use?
Thanks.
Class DataHelper
public class DataHelper {
private static final String DATABASE_NAME = "sms.db";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_NAME = "words";
private Context context;
private SQLiteDatabase db;
private SQLiteStatement insertStmt;
private static final String INSERT = "insert into "
+ TABLE_NAME + "(word) values (?)";
public DataHelper(Context context) {
this.context = context;
OpenHelper openHelper = new OpenHelper(this.context);
this.db = openHelper.getWritableDatabase();
this.insertStmt = this.db.compileStatement(INSERT);
}
public long insert(String word) {
this.insertStmt.bindString(1, word);
return this.insertStmt.executeInsert();
}
public List<String> selectAll() {
List<String> list = new ArrayList<String>();
Cursor cursor = this.db.query(TABLE_NAME, new String[] { "word"},
null, null, null, null, "id desc");
if (cursor.moveToFirst()) {
do {
list.add(cursor.getString(0));
} while (cursor.moveToNext());
}
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
return list;
}
}
Class SMS This is the class where I get the words and insert in database
public class SMS extends Activity {
private DataHelper dh;
private static TextView txtView;
final Uri CONTENT_URI = Uri.parse("content://sms/sent");
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
this.dh = new DataHelper(this);
txtView = (TextView)findViewById(R.id.txtView);
Cursor cursor = getContentResolver().query(CONTENT_URI, null, null, null, null);
String body;
if(cursor.moveToFirst()){
body = cursor.getString(cursor.getColumnIndexOrThrow("body")).toString();
if(body == ""){
Toast.makeText(getBaseContext(), "There is no words to save!", Toast.LENGTH_LONG).show();
}
else{
StringTokenizer st = new StringTokenizer(body);
while(st.hasMoreTokens()){
this.dh.insert(st.nextToken());
Toast.makeText(getBaseContext(), "The set of words has been updated!", Toast.LENGTH_LONG).show();
}
List<String> words = this.dh.selectAll();
StringBuilder sb = new StringBuilder();
sb.append("Set of开发者_StackOverflow社区 words:\n\n");
for (String w : words) {
sb.append(w + " ");
}
Log.d("EXAMPLE", "words size - " + words.size());
txtView.setText(sb.toString());
}
}
}
}
Answer by @MPelletier
You should also rethink your column name "Count", as it is a reserved word for a function.
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