nested loop join

.gitignore

@@ -26,6 +26,7 @@ install_manifest.txt
 compile_commands.json
 CTestTestfile.cmake
 _deps
+_test*
 
 *.db
 deps/

src/db/iterator.rs

@@ -1,3 +1,4 @@
+use crate::db::engine::Session;
 use crate::db::eval::{compare_tuple_by_keys, tuple_eval};
 use crate::db::table::{ColId, TableId, TableInfo};
 use crate::error::CozoError::LogicError;
@@ -25,14 +26,20 @@ impl<'a> Debug for IteratorSlot<'a> {
     }
 }
 
-pub enum TableRowGetter {
+pub enum TableRowGetter<'a> {
     Dummy,
+    Reified {
+        sess: &'a Session<'a>,
+        key_cache: OwnTuple,
+        in_root: bool,
+    },
 }
 
-impl Debug for TableRowGetter {
+impl<'a> Debug for TableRowGetter<'a> {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         match self {
             TableRowGetter::Dummy => write!(f, "DummyRowGetter"),
+            TableRowGetter::Reified { .. } => write!(f, "TableRowGetter"),
         }
     }
 }
@@ -81,12 +88,13 @@ pub enum ExecPlan<'a> {
         it: IteratorSlot<'a>,
         info: TableInfo,
         binding: Option<String>,
-        getter: TableRowGetter,
+        getter: TableRowGetter<'a>,
     },
     ChainJoinItPlan {
         left: Box<ExecPlan<'a>>,
-        right: TableRowGetter,
+        right: TableRowGetter<'a>,
         right_info: TableInfo,
+        right_binding: Option<String>,
         kind: ChainJoinKind,
         left_outer: bool,
         right_outer: bool,
@@ -177,8 +185,11 @@ impl<'a> ExecPlan<'a> {
             ExecPlan::EdgeBwdItPlan { .. } => {
                 todo!()
             }
-            ExecPlan::ChainJoinItPlan { .. } => {
-                todo!()
+            ExecPlan::ChainJoinItPlan {
+                left, right_info, ..
+            } => {
+                let (l1, l2) = left.tuple_widths();
+                (l1 + 1, l2 + 1)
             }
         }
     }

src/db/plan.rs

@@ -6,6 +6,7 @@ use crate::error::CozoError::LogicError;
 use crate::error::Result;
 use crate::parser::Rule;
 use crate::relation::data::DataKind;
+use crate::relation::tuple::OwnTuple;
 use crate::relation::value::{StaticValue, Value};
 use cozorocks::IteratorPtr;
 use pest::iterators::Pair;
@@ -113,7 +114,7 @@ impl<'a> Session<'a> {
                 let amap = match &binding {
                     None => Default::default(),
                     Some(binding) => {
-                        let amap = self.edge_accessor_map(&binding, &info);
+                        let amap = self.edge_accessor_map(binding, &info);
                         convert_to_relative_accessor_map(amap)
                     }
                 };
@@ -189,8 +190,35 @@ impl<'a> Session<'a> {
                 kind,
                 left_outer,
                 right_outer,
+                right_binding,
             } => {
-                todo!()
+                let (l_plan, l_map) = self.do_reify_intermediate_plan(*left)?;
+                let r_map = match &right_binding {
+                    None => Default::default(),
+                    Some(binding) => match kind {
+                        ChainJoinKind::NodeToFwdEdge | ChainJoinKind::NodeToBwdEdge => {
+                            self.edge_accessor_map(binding, &right_info)
+                        }
+                        ChainJoinKind::FwdEdgeToNode | ChainJoinKind::BwdEdgeToNode => {
+                            self.node_accessor_map(binding, &right_info)
+                        }
+                    },
+                };
+                let r_map = shift_accessor_map(r_map, l_plan.tuple_widths());
+                let plan = ExecPlan::ChainJoinItPlan {
+                    left: l_plan.into(),
+                    right: TableRowGetter::Reified {
+                        sess: self,
+                        key_cache: OwnTuple::with_prefix(right_info.table_id.id as u32),
+                        in_root: right_info.table_id.in_root,
+                    },
+                    right_info,
+                    right_binding,
+                    kind,
+                    left_outer,
+                    right_outer,
+                };
+                (plan, merge_accessor_map(l_map, r_map))
             }
         };
         Ok(res)
@@ -295,6 +323,7 @@ impl<'a> Session<'a> {
                         },
                         left_outer: prev_left_outer,
                         right_outer: el.right_outer_marker,
+                        right_binding: el.binding,
                     };
 
                     prev_kind = el.kind;

src/relation/tuple.rs

@@ -19,6 +19,15 @@ where
     idx_cache: RefCell<Vec<usize>>,
 }
 
+impl<T> Tuple<T>
+where
+    T: AsRef<[u8]>,
+{
+    pub fn clear_cache(&self) {
+        self.idx_cache.borrow_mut().clear()
+    }
+}
+
 impl<T> AsRef<[u8]> for Tuple<T>
 where
     T: AsRef<[u8]>,
@@ -482,6 +491,11 @@ impl<'a, T: AsRef<[u8]>> Iterator for TupleIter<'a, T> {
 }
 
 impl OwnTuple {
+    #[inline]
+    pub fn truncate_all(&mut self) {
+        self.clear_cache();
+        self.data.truncate(PREFIX_LEN);
+    }
     #[inline]
     pub fn empty_tuple() -> OwnTuple {
         OwnTuple::with_data_prefix(DataKind::Empty)