Android Database Sqlite Retrieving data with multiple where's

So I'm trying to make my database readable having in consideration that only the "categoria" that where selected are retrieved, so i developed this code:

        plus = praia+ cafe+serv+rest+hot+muse+mon+escolas;
    String dados[] = new String[plus];
//categoria is the name of the colum
    String querry = "categoria = ?";
    for(i=1; i<plus;i++){
        querry = querry+ " OR categoria = ?";
    }
//if == 1 its active if == 0 its unactive;
    if(praia == 1){
        dados[cont]= "Praias";
    }
    if(serv == 1){
        dados[cont]= "Servicos";
    }
    if(cafe == 1){
        dados[cont]= "Cafes";
    }
    if(rest == 1){
        dados[cont]= "Restaurantes";
    }
    if(hot == 1){
        dados[cont]= "Hoteis";
    }
    if(muse == 1){
        dados[cont]= "Museus";
    }
    if(mon == 1){
        dados[cont]= "Monumentos";
    }
    if(escolas == 1){
        dados[cont]= "Escolas";
    }
    String[] projections ={VianaContract.NewLocalInfo.Nome, VianaContract.NewLocalInfo.Categoria, VianaContract.NewLocalInfo.Latitude, VianaContract.NewLocalInfo.Longitude};
    //error here
    cursor = db.query(VianaContract.NewLocalInfo.Table_name,projections,querry, dados, null, null,null);

And this is the logcat:

05-01 07:58:13.131    1435-1435/prosis.guiatour D/AndroidRuntime﹕ Shutting down VM
05-01 07:58:13.131    1435-1435/prosis.guiatour W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0xb3ac7ba8)
 05-01 07:58:13.171    1435-1435/prosis.guiatour E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: prosis.guiatour, PID: 1435
java.lang.RuntimeException: Unable to start activity ComponentInfo{prosis.guiatour/prosis.guiatour.Lista}: java.lang.IllegalArgumentException: the bind value at index 3 is null
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
        at android.app.ActivityThread.access$800(ActivityThread.java:135)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:136)
        at android.app.ActivityThread.main(ActivityThread.java:5017)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:515)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
        at dalvik.system.NativeStart.main(Native Method)
 Caused by: java.lang.IllegalArgumentException: the bind value at index 3 is null
        at android.database.sqlite.SQLiteProgram.bindString(SQLiteProgram.java:164)
        at android.database.sqlite.SQLiteProgram.bindAllArgsAsStrings(SQLiteProgram.java:200)
        at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:47)
        at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314)
        at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1161)
        at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1032)
        at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1200)
        at prosis.guiatour.VianaDbHelper.getInfor(VianaDbHelper.java:123)
        at prosis.guiatour.Lista.onCreate(Lista.java:49)
        at android.app.Activity.performCreate(Activity.java:5231)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)    at android.app.ActivityThread.access$800(ActivityThread.java:135)    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)    at android.os.Handler.dispatchMessage(Handler.java:102)    at android.os.Looper.loop(Looper.java:136)    at android.app.ActivityThread.main(ActivityThread.java:5017)    at java.lang.reflect.Method.invokeNative(Native Method)    at java.lang.reflect.Method.invoke(Method.java:515)    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)    at dalvik.system.NativeStart.main(Native Method)

What do you think is causing the error ?