diff --git a/crates/ra_db/src/lib.rs b/crates/ra_db/src/lib.rs
index 4bfc3f9ae94..cab47dcacce 100644
--- a/crates/ra_db/src/lib.rs
+++ b/crates/ra_db/src/lib.rs
@@ -80,14 +80,6 @@ pub trait FilesDatabase: salsa::Database + CheckCanceled {
     #[salsa::input]
     fn source_root(&self, id: SourceRootId) -> Arc<SourceRoot>;
     fn source_root_crates(&self, id: SourceRootId) -> Arc<Vec<CrateId>>;
-    /// The set of "local" (that is, from the current workspace) roots.
-    /// Files in local roots are assumed to change frequently.
-    #[salsa::input]
-    fn local_roots(&self) -> Arc<Vec<SourceRootId>>;
-    /// The set of roots for crates.io libraries.
-    /// Files in libraries are assumed to never change.
-    #[salsa::input]
-    fn library_roots(&self) -> Arc<Vec<SourceRootId>>;
     /// The crate graph.
     #[salsa::input]
     fn crate_graph(&self) -> Arc<CrateGraph>;
diff --git a/crates/ra_hir/src/mock.rs b/crates/ra_hir/src/mock.rs
index 4af4dd096e5..cfbe652b0ab 100644
--- a/crates/ra_hir/src/mock.rs
+++ b/crates/ra_hir/src/mock.rs
@@ -140,8 +140,6 @@ impl Default for MockDatabase {
             file_counter: 0,
         };
         db.set_crate_graph(Default::default());
-        db.set_local_roots(Default::default());
-        db.set_library_roots(Default::default());
         db
     }
 }
diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index 02e12437c3a..119190e0aa5 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -1,11 +1,11 @@
 use std::sync::Arc;
 
 use ra_db::{
-    CheckCanceled, FileId, Canceled,
-    salsa::{self, Database},
+    CheckCanceled, FileId, Canceled, FilesDatabase,
+    salsa,
 };
 
-use crate::{symbol_index, LineIndex};
+use crate::{LineIndex, symbol_index::{self, SymbolsDatabase}};
 
 #[salsa::database(
     ra_db::FilesDatabaseStorage,
@@ -34,12 +34,9 @@ impl Default for RootDatabase {
             runtime: salsa::Runtime::default(),
             interner: Default::default(),
         };
-        db.query_mut(ra_db::CrateGraphQuery)
-            .set((), Default::default());
-        db.query_mut(ra_db::LocalRootsQuery)
-            .set((), Default::default());
-        db.query_mut(ra_db::LibraryRootsQuery)
-            .set((), Default::default());
+        db.set_crate_graph(Default::default());
+        db.set_local_roots(Default::default());
+        db.set_library_roots(Default::default());
         db
     }
 }
diff --git a/crates/ra_ide_api/src/symbol_index.rs b/crates/ra_ide_api/src/symbol_index.rs
index e073a349ef3..4d81d14b3f0 100644
--- a/crates/ra_ide_api/src/symbol_index.rs
+++ b/crates/ra_ide_api/src/symbol_index.rs
@@ -49,6 +49,14 @@ pub(crate) trait SymbolsDatabase: hir::db::HirDatabase {
     fn file_symbols(&self, file_id: FileId) -> Arc<SymbolIndex>;
     #[salsa::input]
     fn library_symbols(&self, id: SourceRootId) -> Arc<SymbolIndex>;
+    /// The set of "local" (that is, from the current workspace) roots.
+    /// Files in local roots are assumed to change frequently.
+    #[salsa::input]
+    fn local_roots(&self) -> Arc<Vec<SourceRootId>>;
+    /// The set of roots for crates.io libraries.
+    /// Files in libraries are assumed to never change.
+    #[salsa::input]
+    fn library_roots(&self) -> Arc<Vec<SourceRootId>>;
 }
 
 fn file_symbols(db: &impl SymbolsDatabase, file_id: FileId) -> Arc<SymbolIndex> {