op rederive for views

README.md

@@ -1,10 +1,5 @@
 ## TODO
 
-* [ ] stored relations
-  * [ ] `store-put` and `store-retract`
 * [ ] more complete functions and aggregations
-* [ ] auto-updating relations?
-  * [ ] counting-based `auto-view`
-  * [ ] manual or time-based `materialized-view`
 * [ ] more complete tx tests
 * [ ] graph algorithms

src/parse/query.rs

@@ -54,6 +54,7 @@ impl TryFrom<&'_ JsonValue> for SortDir {
 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
 pub(crate) enum ViewOp {
     Create,
+    Rederive,
     Put,
     Retract,
 }
@@ -225,6 +226,8 @@ impl SessionTx {
                     .ok_or_else(|| anyhow!("view options must be an object"))?;
                 let (op, name) = if let Some(name) = opts.get("create") {
                     (ViewOp::Create, name)
+                } else if let Some(name) = opts.get("rederive") {
+                    (ViewOp::Rederive, name)
                 } else if let Some(name) = opts.get("put") {
                     (ViewOp::Put, name)
                 } else if let Some(name) = opts.get("retract") {

src/query/pull.rs

@@ -91,12 +91,23 @@ impl SessionTx {
         op: ViewOp,
         meta: &ViewRelMetadata,
     ) -> Result<()> {
-        let view_store = if op == ViewOp::Create {
+        if op == ViewOp::Rederive {
+            let _ = self.destroy_view_rel(&meta.name);
+        }
+        let view_store = if op == ViewOp::Rederive || op == ViewOp::Create {
             self.create_view_rel(meta.clone())?
         } else {
             let found = self.get_view_rel(&meta.name)?;
-            ensure!(found.metadata.arity == meta.arity, "arity mismatch for view {}", meta.name);
+            ensure!(
-            ensure!(found.metadata.kind == meta.kind, "kind mismatch for view {:?}", meta.kind);
+                found.metadata.arity == meta.arity,
+                "arity mismatch for view {}",
+                meta.name
+            );
+            ensure!(
+                found.metadata.kind == meta.kind,
+                "kind mismatch for view {:?}",
+                meta.kind
+            );
             found
         };
         let mut vtx = self.view_db.transact().start();

src/runtime/db.rs

@@ -313,7 +313,7 @@ impl Db {
                     "view '{}' exists but is required not to be",
                     meta.name
                 )
-            } else {
+            } else if *op != ViewOp::Rederive {
                 ensure!(
                     tx.view_exists(&meta.name)?,
                     "view '{}' does not exist but is required to be",

tests/air_routes.rs

@@ -69,7 +69,7 @@ fn air_routes() -> Result<()> {
     let view_time = Instant::now();
     match db.run_script(r#"
         ?[?src, ?dst, ?distance] := [?r route.src ?src], [?r route.dst ?dst], [?r route.distance ?distance];
-        :view create flies_to;
+        :view rederive flies_to;
     "#) {
         Ok(_) => {dbg!(view_time.elapsed());}
         Err(_) => {
@@ -1237,7 +1237,7 @@ fn air_routes() -> Result<()> {
      [11758,["LHR","NRT","AKL","BHE"]],[11751,["LHR","NRT","AKL","NSN"]]]
     "#
         )
-            .unwrap()
+        .unwrap()
     );
 
     Ok(())