seq scan initial implementation

1 files changed, 24 insertions, 0 deletions

diff --git a/lib/planner.ml b/lib/planner.ml
new file mode 100644
index 0000000..ceaf815
--- /dev/null
+++ b/lib/planner.ml
@@ -0,0 +1,24 @@
+module Scan = struct
+  open Disk
+  let execute commit locations (entity: string) =
+    Executor.read commit locations ~filename:entity
+end
+
+module Join = struct
+  open Disk
+  let execute (left_attributes: bytes list) (right_attributes: bytes list) locations =
+    (* Redundant operations that are already in the locations, but this is easier to implement now *)
+    (* Fix this when we persist the indexes *)
+    let left_computed_hashes: (int * string) list = List.mapi (fun index elem -> (index, Interop.Sha256.compute_hash elem)) left_attributes in
+    let right_computed_hashes: (int * string) list = List.mapi (fun index elem -> (index, Interop.Sha256.compute_hash elem)) right_attributes in
+    let references_locations_right = List.filter_map (fun (index, rhash) -> Option.map (fun (elem: Executor.Location.t) -> index, rhash, elem.references)
+                                                                            @@ Executor.StringMap.find_opt rhash locations) right_computed_hashes in
+    let indexes =
+      List.filter_map (fun (lindex, lhash) -> Option.map (fun (rindex, rhash, _) -> lindex, rindex, lhash, rhash)
+                                              @@ List.find_opt (fun (_rindex, _rhash, references) -> List.exists ((=) lhash) references) references_locations_right) left_computed_hashes
+    in List.map (fun (lindex, rindex, _, _) -> List.nth left_attributes lindex, List.nth right_attributes rindex) indexes
+  
+end
+
+module Filter = struct
+end