Reputation: 3306
I have a SQLite table content with following columns:
-----------------------------------------------
|id|book_name|chapter_nr|verse_nr|word_nr|word|
-----------------------------------------------
the sql query
select count(*) from content where book_name = 'John'
group by book_name, chapter_nr
in DB Browser returns 21 rows (which is the count of chapters)
the equivalent with ORMLite android:
long count = getHelper().getWordDao().queryBuilder()
.groupByRaw("book_name, chapter_nr")
.where()
.eq("book_name", book_name)
.countOf();
returns 828 rows (which is the count of verse numbers)
as far as I know the above code is translated to:
select count(*) from content
where book_name = 'John'
group by book_name, chapter_nr
result of this in DB Browser:
| count(*)
------------
1 | 828
2 | 430
3 | 653
...
21| 542
---------
21 Rows returned from: select count(*)...
so it seems to me that ORMLite returns the first row of the query as the result of countOf()
.
I've searched stackoverflow and google a lot. I found this question (and more interestingly the answer)
You can also count the number of rows in a custom query by calling the > countOf() method on the Where or QueryBuilder object.
// count the number of lines in this custom query int numRows = dao.queryBuilder().where().eq("name", "Joe Smith").countOf();
this is (correct me if I'm wrong) exactly what I'm doing, but somehow I just get the wrong number of rows.
So... either I'm doing something wrong here or countOf()
is not working the way it is supposed to.
Note: It's the same with groupBy
instead of groupByRaw
(according to ORMLite documentation joining groupBy's should work)
...
.groupBy("book_name")
.groupBy("chapter_nr")
.where(...)
.countOf()
EDIT: getWordDao
returns from class Word
:
@DatabaseTable(tableName = "content")
public class Word { ... }
Upvotes: 3
Views: 1632
Reputation: 116888
returns 828 rows (which is the count of verse numbers)
This seems to be a limitation of the QueryBuilder.countOf()
mechanism. It is expecting a single value and does not understand the addition of GROUP BY
to the count query. You can tell that it doesn't because that method returns a single long
.
If you want to extract the counts for each of the groups it looks like you will need to do a raw query check out the docs.
Upvotes: 1