diff --git a/crates/ra_db/src/lib.rs b/crates/ra_db/src/lib.rs
index cab47dcacc..2664dc69a2 100644
--- a/crates/ra_db/src/lib.rs
+++ b/crates/ra_db/src/lib.rs
@@ -63,8 +63,10 @@ pub struct FileRange {
     pub range: TextRange,
 }
 
-#[salsa::query_group(FilesDatabaseStorage)]
-pub trait FilesDatabase: salsa::Database + CheckCanceled {
+/// Database which stores all significant input facts: source code and project
+/// model. Everything else in rust-analyzer is derived from these queries.
+#[salsa::query_group(SourceDatabaseStorage)]
+pub trait SourceDatabase: salsa::Database + CheckCanceled {
     /// Text of the file.
     #[salsa::input]
     fn file_text(&self, file_id: FileId) -> Arc<String>;
@@ -85,7 +87,7 @@ pub trait FilesDatabase: salsa::Database + CheckCanceled {
     fn crate_graph(&self) -> Arc<CrateGraph>;
 }
 
-fn source_root_crates(db: &impl FilesDatabase, id: SourceRootId) -> Arc<Vec<CrateId>> {
+fn source_root_crates(db: &impl SourceDatabase, id: SourceRootId) -> Arc<Vec<CrateId>> {
     let root = db.source_root(id);
     let graph = db.crate_graph();
     let res = root
@@ -96,7 +98,7 @@ fn source_root_crates(db: &impl FilesDatabase, id: SourceRootId) -> Arc<Vec<Crat
     Arc::new(res)
 }
 
-fn source_file(db: &impl FilesDatabase, file_id: FileId) -> TreeArc<SourceFile> {
+fn source_file(db: &impl SourceDatabase, file_id: FileId) -> TreeArc<SourceFile> {
     let text = db.file_text(file_id);
     SourceFile::parse(&*text)
 }
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index 1bb9e03056..9b5b79d38d 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -1,7 +1,7 @@
 use std::sync::Arc;
 
 use ra_syntax::{SyntaxNode, TreeArc, SourceFile};
-use ra_db::{FilesDatabase, CrateId, salsa};
+use ra_db::{SourceDatabase, CrateId, salsa};
 
 use crate::{
     MacroCallId, HirFileId,
@@ -19,7 +19,7 @@ use crate::{
 };
 
 #[salsa::query_group(HirDatabaseStorage)]
-pub trait HirDatabase: FilesDatabase + AsRef<HirInterner> {
+pub trait HirDatabase: SourceDatabase + AsRef<HirInterner> {
     #[salsa::invoke(HirFileId::hir_source_file)]
     fn hir_source_file(&self, file_id: HirFileId) -> TreeArc<SourceFile>;
 
diff --git a/crates/ra_hir/src/mock.rs b/crates/ra_hir/src/mock.rs
index cfbe652b0a..7da15eca01 100644
--- a/crates/ra_hir/src/mock.rs
+++ b/crates/ra_hir/src/mock.rs
@@ -2,7 +2,7 @@ use std::{sync::Arc, panic};
 
 use parking_lot::Mutex;
 use ra_db::{
-    CheckCanceled, FilePosition, FileId, CrateGraph, SourceRoot, SourceRootId, FilesDatabase, salsa,
+    CheckCanceled, FilePosition, FileId, CrateGraph, SourceRoot, SourceRootId, SourceDatabase, salsa,
 };
 use relative_path::RelativePathBuf;
 use test_utils::{parse_fixture, CURSOR_MARKER, extract_offset};
@@ -11,7 +11,7 @@ use crate::{db, HirInterner};
 
 pub const WORKSPACE: SourceRootId = SourceRootId(0);
 
-#[salsa::database(ra_db::FilesDatabaseStorage, db::HirDatabaseStorage)]
+#[salsa::database(ra_db::SourceDatabaseStorage, db::HirDatabaseStorage)]
 #[derive(Debug)]
 pub(crate) struct MockDatabase {
     events: Mutex<Option<Vec<salsa::Event<MockDatabase>>>>,
diff --git a/crates/ra_hir/src/nameres/tests.rs b/crates/ra_hir/src/nameres/tests.rs
index 24936976c2..e72781f512 100644
--- a/crates/ra_hir/src/nameres/tests.rs
+++ b/crates/ra_hir/src/nameres/tests.rs
@@ -1,6 +1,6 @@
 use std::sync::Arc;
 
-use ra_db::{CrateGraph, SourceRootId, FilesDatabase};
+use ra_db::{CrateGraph, SourceRootId, SourceDatabase};
 use relative_path::RelativePath;
 use test_utils::{assert_eq_text, covers};
 
diff --git a/crates/ra_hir/src/ty/tests.rs b/crates/ra_hir/src/ty/tests.rs
index a56783b6e6..0eb4da06e7 100644
--- a/crates/ra_hir/src/ty/tests.rs
+++ b/crates/ra_hir/src/ty/tests.rs
@@ -1,7 +1,7 @@
 use std::sync::Arc;
 use std::fmt::Write;
 
-use ra_db::{FilesDatabase, salsa::Database};
+use ra_db::{SourceDatabase, salsa::Database};
 use ra_syntax::ast::{self, AstNode};
 
 use crate::{
diff --git a/crates/ra_ide_api/src/call_info.rs b/crates/ra_ide_api/src/call_info.rs
index 0eb70df162..728f2df300 100644
--- a/crates/ra_ide_api/src/call_info.rs
+++ b/crates/ra_ide_api/src/call_info.rs
@@ -1,4 +1,4 @@
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 use ra_syntax::{
     AstNode, SyntaxNode, TextUnit, TextRange,
     SyntaxKind::FN_DEF,
diff --git a/crates/ra_ide_api/src/completion.rs b/crates/ra_ide_api/src/completion.rs
index 581ba5de81..be64f2c5a2 100644
--- a/crates/ra_ide_api/src/completion.rs
+++ b/crates/ra_ide_api/src/completion.rs
@@ -9,7 +9,7 @@ mod complete_path;
 mod complete_scope;
 mod complete_postfix;
 
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 
 use crate::{
     db,
diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index 119190e0aa..3da93ec35b 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -1,14 +1,14 @@
 use std::sync::Arc;
 
 use ra_db::{
-    CheckCanceled, FileId, Canceled, FilesDatabase,
+    CheckCanceled, FileId, Canceled, SourceDatabase,
     salsa,
 };
 
 use crate::{LineIndex, symbol_index::{self, SymbolsDatabase}};
 
 #[salsa::database(
-    ra_db::FilesDatabaseStorage,
+    ra_db::SourceDatabaseStorage,
     LineIndexDatabaseStorage,
     symbol_index::SymbolsDatabaseStorage,
     hir::db::HirDatabaseStorage
@@ -59,11 +59,11 @@ impl AsRef<hir::HirInterner> for RootDatabase {
 }
 
 #[salsa::query_group(LineIndexDatabaseStorage)]
-pub(crate) trait LineIndexDatabase: ra_db::FilesDatabase + CheckCanceled {
+pub(crate) trait LineIndexDatabase: ra_db::SourceDatabase + CheckCanceled {
     fn line_index(&self, file_id: FileId) -> Arc<LineIndex>;
 }
 
-fn line_index(db: &impl ra_db::FilesDatabase, file_id: FileId) -> Arc<LineIndex> {
+fn line_index(db: &impl ra_db::SourceDatabase, file_id: FileId) -> Arc<LineIndex> {
     let text = db.file_text(file_id);
     Arc::new(LineIndex::new(&*text))
 }
diff --git a/crates/ra_ide_api/src/extend_selection.rs b/crates/ra_ide_api/src/extend_selection.rs
index bc19b0b9d9..1cd9553577 100644
--- a/crates/ra_ide_api/src/extend_selection.rs
+++ b/crates/ra_ide_api/src/extend_selection.rs
@@ -1,4 +1,4 @@
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 use ra_syntax::{
     SyntaxNode, AstNode, SourceFile,
     ast, algo::find_covering_node,
diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 0e40e35cef..180cc7c809 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -1,4 +1,4 @@
-use ra_db::{FileId, FilesDatabase};
+use ra_db::{FileId, SourceDatabase};
 use ra_syntax::{
     AstNode, ast,
     algo::find_node_at_offset,
diff --git a/crates/ra_ide_api/src/hover.rs b/crates/ra_ide_api/src/hover.rs
index 04f5a746e7..b6d727399b 100644
--- a/crates/ra_ide_api/src/hover.rs
+++ b/crates/ra_ide_api/src/hover.rs
@@ -1,4 +1,4 @@
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 use ra_syntax::{
     AstNode, SyntaxNode, TreeArc, ast,
     algo::{find_covering_node, find_node_at_offset, find_leaf_at_offset, visit::{visitor, Visitor}},
diff --git a/crates/ra_ide_api/src/imp.rs b/crates/ra_ide_api/src/imp.rs
index f2d41321dc..1222fdc449 100644
--- a/crates/ra_ide_api/src/imp.rs
+++ b/crates/ra_ide_api/src/imp.rs
@@ -4,7 +4,7 @@ use hir::{
     self, Problem, source_binder
 };
 use ra_db::{
-    FilesDatabase, SourceRoot, SourceRootId,
+    SourceDatabase, SourceRoot, SourceRootId,
     salsa::{Database, SweepStrategy},
 };
 use ra_ide_api_light::{self, assists, LocalEdit, Severity};
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index 8380aa6c29..62a1934f41 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -34,7 +34,7 @@ use std::{fmt, sync::Arc};
 use ra_syntax::{SourceFile, TreeArc, TextRange, TextUnit};
 use ra_text_edit::TextEdit;
 use ra_db::{
-    FilesDatabase, CheckCanceled,
+    SourceDatabase, CheckCanceled,
     salsa::{self, ParallelDatabase},
 };
 use rayon::prelude::*;
diff --git a/crates/ra_ide_api/src/rename.rs b/crates/ra_ide_api/src/rename.rs
index fe81609df9..81ca0537c3 100644
--- a/crates/ra_ide_api/src/rename.rs
+++ b/crates/ra_ide_api/src/rename.rs
@@ -17,7 +17,7 @@ use crate::{
     SourceChange,
     SourceFileEdit,
 };
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 use relative_path::RelativePath;
 
 pub(crate) fn rename(
diff --git a/crates/ra_ide_api/src/runnables.rs b/crates/ra_ide_api/src/runnables.rs
index e21724207a..0f2d00f134 100644
--- a/crates/ra_ide_api/src/runnables.rs
+++ b/crates/ra_ide_api/src/runnables.rs
@@ -3,7 +3,7 @@ use ra_syntax::{
     TextRange, SyntaxNode,
     ast::{self, AstNode, NameOwner, ModuleItemOwner},
 };
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 
 use crate::{db::RootDatabase, FileId};
 
diff --git a/crates/ra_ide_api/src/symbol_index.rs b/crates/ra_ide_api/src/symbol_index.rs
index 4d81d14b3f..230ff410eb 100644
--- a/crates/ra_ide_api/src/symbol_index.rs
+++ b/crates/ra_ide_api/src/symbol_index.rs
@@ -34,7 +34,7 @@ use ra_syntax::{
     ast::{self, NameOwner},
 };
 use ra_db::{
-    SourceRootId, FilesDatabase,
+    SourceRootId, SourceDatabase,
     salsa::{self, ParallelDatabase},
 };
 use rayon::prelude::*;
diff --git a/crates/ra_ide_api/src/syntax_highlighting.rs b/crates/ra_ide_api/src/syntax_highlighting.rs
index cfa0257dd2..16d23e140e 100644
--- a/crates/ra_ide_api/src/syntax_highlighting.rs
+++ b/crates/ra_ide_api/src/syntax_highlighting.rs
@@ -1,5 +1,5 @@
 use ra_syntax::{ast, AstNode,};
-use ra_db::FilesDatabase;
+use ra_db::SourceDatabase;
 
 use crate::{
     FileId, HighlightedRange,