在SQLiteDatabase中找不到记录

Question

In my application, I create a table for my database like this :

    String action;

    action= "CREATE TABLE ";
    action+=TABLE_LIEUX;
    action+="(Name TEXT NOT NULL PRIMARY KEY);";
    base.execSQL(action);

I then add a record to this table with :

    ContentValues valeur;
    long InsertLine=-10;

    valeur=new ContentValues(1);
    valeur.put("Name","'"+name+"'");
    InsertLine=getWritableDatabase().insert(TABLE_LIEUX,null,valeur);

The value I get for InsertLine is 1, as expected. But when I try to search for the row added with :

            result=(SQLiteCursor)getWritableDatabase().query(TABLE_LIEUX,null,"Name='"+name+"'",null,null,null,null);

the SQLiteCursor result I get has a length of -1. And when I try to add the row again, I get an SQLiteException which indicates the row should be unique (so, despite the result of the search, the row is already in the database).

Any idea?

Answer 1

You must force the Cursor to read the returned data (by calling moveToFirst or something like that) before you can get the cursor's record count.

Furthermore, you must not quote values when using the ContentValues put function; the value in the database now contains superfluous quotes.

Answer 2

Why did you cast your query result to (SQLiteCursor)? Query statements always return a Cursor object so bother with the cast.

 Cursor result = getWritableDatabase().
 query(TABLE_LIEUX, null, "Name='"+name+
"'", null, null, null, null);

String mString;

if(result != null && c.moveToFirst()) {
     mString = result.getString(result.
 getColumnIndex("Name"));
}

hope this helps.