Use "where in" for LiteDB

Question

I enjoy working with LiteDB in Xamarin.Forms. What is the best practice for getting list of objects from a table using list of ids or indexes in condition? Currently, it looks for me like this:

_db.GetCollection<T>().FindAll().Where(q => listValues.Contains(Convert.ToInt32(q.GetProperty(idColumnName))));

listValues - list of searched ids. idColumnName - column with indexes.

But FindAll retrives all records from LiteDB. Is there any more efficint options without full scanning?

score 4 · Answer 1 · answered Apr 06 '18 at 09:29

4

Use the query in the Find method instead which will only retrieve entries based on your query rather than the full data set. This, according to the LiteDB's guidance, is more efficient than Linq queries on the full data returned: https://github.com/mbdavid/LiteDB/wiki/Queries

So your query would look like as follows

_d.GetCollection<T>().Find(q => listValues.Contains(Convert.ToInt32(q.GetProperty(idColumnName))))

answered Apr 06 '18 at 09:29

MBT86

51
4

Thank you for the reply. I'll try that. – Serg Apr 08 '18 at 20:20

score 0 · Answer 2 · answered Jul 22 '22 at 18:03

0

I think you can just use collection.Query().Where("Column", 1,2,3) for this

answered Jul 22 '22 at 18:03

YoCom

21
4

Use "where in" for LiteDB

2 Answers2