many to many - Linq query, a connection table issue -
i want write query presents every event (tbl_events) objects (tbl_objects) related him (relation type — m:n).
i have problem tables connection tables (association class) holds foreign keys of 2 tables connects.
for intance, tbl_events connected connection table named tbl_object_has_tbl_events tbl_objects.
here structure of connected tables:
tbl events has: eventid, eventname tbl_object has: objectid, objectname tbl_object_has_tbl_events: eventid, objectid
here tried write:
ilist datalist = (from devent in app.gliduscontext.tbl_events. join dobject in app.gliduscontext.tbl_objects on devent.tbl_objects equals dobject.objectid select new { devent.eventname, dobject.objectname}).tolist();
i can't reach connection table tbl_object_has_tbl_events
my question how can implement such query, when have m:n relationship.
thanks.
update generation of many-to-many relationship:
-- ----------------------------------------------------- -- table tbl_events -- ----------------------------------------------------- create table tbl_events ( eventid int not null identity, eventname nvarchar(100) not null, primary key (eventid)); -- ----------------------------------------------------- -- table tbl_objects -- ----------------------------------------------------- create table tbl_objects ( objectid int not null identity, objectname nvarchar(100) not null, primary key (objectid)); -- ----------------------------------------------------- -- table tbl_objects_has_tbl_events -- ----------------------------------------------------- create table tbl_objects_has_tbl_events ( objectid int not null, eventid int not null, primary key (objectid, eventid), constraint fk_tbl_objects_has_tbl_events_tbl_objects foreign key (objectid) references tbl_objects (objectid) on delete cascade on update cascade, constraint fk_tbl_objects_has_tbl_events_tbl_events foreign key (eventid) references tbl_events (eventid) on delete cascade on update cascade);
the entity data model doesn't show tables contain fk's. in case events entity have navigation property objects , object entity have navigation property events.
so information write query this:
ilist datalist = (from devent in app.gliduscontext.tbl_events dobject in devent.objects select new { devent.eventname, dobject.objectname}).tolist();
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