sqlite query execution when button is clicked in android

Question

I have a databaseHelper class. But, I want to multiply two values of each row and store it in another column while a button is clicked. I have checked my query and it works fine but I want to directly multiply the values and make change in the database when a button is click. I don't want to return any values but simply execute the query.

What I did for this is I have created a method in my database helper class. This is the method:

public void getTicketTotal(){
    SQLiteDatabase db=this.getWritableDatabase();
    db.rawQuery("update ticket_table set total=quantity*item_price ",null);
}

and in the button click event I did this. But, it didn't multiply and store the values in the table:

 myDb=new DatabaseHelper(TicketActivity.this);

                myDb.getTicketTotal();

What to do?

try using db. execSQL instead of db.rawQuery. It is used when you are expecting some results in return — Gautam, Feb 14 '17 at 09:48
FYI, You are using `UPDATE` query then where is `WHERE ` statement ? — IntelliJ Amiya, Feb 14 '17 at 09:48
`"update ticket_table set total=quantity*item_price "` , this is just a string. It won't multiply — Vivek Mishra, Feb 14 '17 at 09:52

score 1 · Answer 1 · answered Feb 14 '17 at 10:36

1

The problem was with the method that I was using. The solution is to use db.execSQL instead of rawQuery. So the line of code would be:

public void getTicketTotal(){
    SQLiteDatabase db=this.getWritableDatabase();
     db.execSQL("update ticket_table set total=quantity*item_price ");
}

and simply call it from within the activity.

answered Feb 14 '17 at 10:36

Soumya Rauth

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good. So annoying. Sorry bro will not got this. Thanks – Zaki Pathan Feb 14 '17 at 10:38
It's totally ok bro. :) The great part is we actually learned something. – Soumya Rauth Feb 14 '17 at 10:40
1

yes bro :) happy to talk with you – Zaki Pathan Feb 14 '17 at 10:40

score 0 · Answer 2 · edited Feb 14 '17 at 10:09

0

your update query is wrong. on which row you have to update total?

hope it helps

public void getTicketTotal(){
      SQLiteDatabase db=this.getWritableDatabase();
      db.rawQuery("update ticket_table tt set total= tt.quantity * tt.item_price" ,null);
    }

edited Feb 14 '17 at 10:09

Ankush Bist

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answered Feb 14 '17 at 09:50

Zaki Pathan

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But this query works fine while I am separately applying it in my db table. – Soumya Rauth Feb 14 '17 at 09:52
Why do I need a where statement here? – Soumya Rauth Feb 14 '17 at 09:52
Because you want to update on single data right? So you need to set WHERE condition. Like "WHERE Id = 3" – Zaki Pathan Feb 14 '17 at 09:54
I think it helps you. If this helps mark this as a right answer. Thanks Bro – Zaki Pathan Feb 14 '17 at 09:56
@ZakiPathan where clause is not mandatory. – Ankush Bist Feb 14 '17 at 09:57
No bro, not single data. I want to change it on every row – Soumya Rauth Feb 14 '17 at 09:57
So you dont need WHERE clause. You just try without where clause. I am editing my answer – Zaki Pathan Feb 14 '17 at 09:58
Hope it helps now. – Zaki Pathan Feb 14 '17 at 09:59
quantity and item_price are two columns in my table. Why do I need to fetch it from database and store it in my code? Why can't I simply apply the operation into my database. I mean there are already quantity and item_price data available in the table. – Soumya Rauth Feb 14 '17 at 10:01
So you need to change the query. update ticket_table tt set total= tt.quantity * tt.item_price – Zaki Pathan Feb 14 '17 at 10:02
I edit my answer. Please check if it works – Zaki Pathan Feb 14 '17 at 10:03
I guess that's what I did. – Soumya Rauth Feb 14 '17 at 10:03
Bro, u seem to miss it all. There is still two variable (quantity and item_price ) in your code. Why do I need them? I don't want to pass quantity and item_price from code. The values are already in the table. – Soumya Rauth Feb 14 '17 at 10:06
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/135667/discussion-between-zaki-pathan-and-soumya-rauth). – Zaki Pathan Feb 14 '17 at 10:07
Got any idea bro? – Zaki Pathan Feb 14 '17 at 10:34

sqlite query execution when button is clicked in android

2 Answers2