version: 1.0.98

GEMINI.md

@@ -23,6 +23,12 @@ To support high-throughput operations while allowing for runtime updates (e.g.,
 3. **Immutable AST Caching**: The `Validator` struct immutably owns the `Database` registry. Schemas themselves are frozen structurally, but utilize `OnceLock` interior mutability during the Compilation Phase to permanently cache resolved `$ref` inheritances, properties, and `compiled_edges` directly onto their AST nodes. This guarantees strict `O(1)` relationship and property validation execution at runtime without locking or recursive DB polling.
 4. **Lock-Free Reads**: Incoming operations acquire a read lock just long enough to clone the `Arc` inside an `RwLock<Option<Arc<Validator>>>`, ensuring zero blocking during schema updates.
 
+### Relational Edge Resolution
+When compiling nested object graphs or arrays, the JSPG engine must dynamically infer which Postgres Foreign Key constraint correctly bridges the parent to the nested schema. It utilizes a strict 3-step hierarchical resolution:
+1.  **Direct Prefix Match**: If an explicitly prefixed Foreign Key (e.g. `fk_invoice_counterparty_entity` -> `prefix: "counterparty"`) matches the exact name of the requested schema property (e.g. `{"counterparty": {...}}`), it is instantly selected.
+2.  **Base Edge Fallback (1:M)**: If no explicit prefix directly matches the property name, the compiler filters for explicitly one remaining relation with a `null` prefix (e.g. `fk_invoice_line_invoice` -> `prefix: null`). A `null` prefix mathematically denotes the standard structural parent-child ownership edge (bypassing any M:M ambiguity) and is safely picked over explicit (but unmatched) property edges.
+3.  **Ambiguity Elimination (M:M)**: If multiple explicitly prefixed relations remain (which happens by design in Many-to-Many junction tables like `contact` utilizing `fk_relationship_source` and `fk_relationship_target`), the compiler uses a process of elimination. It checks which of the prefix names the child schema *natively consumes* as an outbound property (e.g. `contact` defines `{ "target": ... }`). It considers that prefix "used up" and mathematically deduces the *remaining* explicitly prefixed relation (`"source"`) must be the inbound link from the parent.
+
 ### Global API Reference
 These functions operate on the global `GLOBAL_JSPG` engine instance and provide administrative boundaries:
 

fixtures/merger.json

@@ -1152,6 +1152,69 @@
                     ]
                 }
             },
+            {
+                "description": "Replace existing person with id and no changes (lookup)",
+                "action": "merge",
+                "data": {
+                    "id": "33333333-3333-3333-3333-333333333333",
+                    "type": "person",
+                    "first_name": "LookupFirst",
+                    "last_name": "LookupLast",
+                    "date_of_birth": "1990-01-01T00:00:00Z",
+                    "pronouns": "they/them"
+                },
+                "mocks": [
+                    {
+                        "id": "22222222-2222-2222-2222-222222222222",
+                        "type": "person",
+                        "first_name": "LookupFirst",
+                        "last_name": "LookupLast",
+                        "date_of_birth": "1990-01-01T00:00:00Z",
+                        "pronouns": "they/them",
+                        "contact_id": "old-contact"
+                    }
+                ],
+                "schema_id": "person",
+                "expect": {
+                    "success": true,
+                    "sql": [
+                        [
+                            "SELECT to_jsonb(t1.*) || to_jsonb(t2.*) || to_jsonb(t3.*) || to_jsonb(t4.*)",
+                            "FROM agreego.\"person\" t1",
+                            "LEFT JOIN agreego.\"user\" t2 ON t2.id = t1.id",
+                            "LEFT JOIN agreego.\"organization\" t3 ON t3.id = t1.id",
+                            "LEFT JOIN agreego.\"entity\" t4 ON t4.id = t1.id",
+                            "WHERE",
+                            "    t1.id = '33333333-3333-3333-3333-333333333333'",
+                            "    OR (",
+                            "        \"first_name\" = 'LookupFirst'",
+                            "        AND \"last_name\" = 'LookupLast'",
+                            "        AND \"date_of_birth\" = '1990-01-01T00:00:00Z'",
+                            "        AND \"pronouns\" = 'they/them'",
+                            "    )"
+                        ],
+                        [
+                            "SELECT pg_notify('entity', '{",
+                            "        \"complete\":{",
+                            "            \"contact_id\":\"old-contact\",",
+                            "            \"date_of_birth\":\"1990-01-01T00:00:00Z\",",
+                            "            \"first_name\":\"LookupFirst\",",
+                            "            \"id\":\"22222222-2222-2222-2222-222222222222\",",
+                            "            \"last_name\":\"LookupLast\",",
+                            "            \"modified_at\":\"2026-03-10T00:00:00Z\",",
+                            "            \"modified_by\":\"00000000-0000-0000-0000-000000000000\",",
+                            "            \"pronouns\":\"they/them\",",
+                            "            \"type\":\"person\"",
+                            "        },",
+                            "        \"new\":{",
+                            "            \"type\":\"person\"",
+                            "        },",
+                            "        \"replaces\":\"33333333-3333-3333-3333-333333333333\"",
+                            "    }')"
+                        ]
+                    ]
+                }
+            },
             {
                 "description": "Update existing person with id (no lookup)",
                 "action": "merge",

fixtures/queryer.json

@@ -27,7 +27,9 @@
             {
               "$id": "get_orders.response",
               "type": "array",
-              "items": { "$ref": "light.order" }
+              "items": {
+                "$ref": "light.order"
+              }
             }
           ]
         }
@@ -77,8 +79,23 @@
           "destination_type": "person",
           "destination_columns": [
             "id"
+          ]
+        },
+        {
+          "id": "22222222-2222-2222-2222-222222222227",
+          "type": "relation",
+          "constraint": "fk_order_counterparty_entity",
+          "source_type": "order",
+          "source_columns": [
+            "counterparty_id",
+            "counterparty_type"
           ],
-          "prefix": "customer"
+          "destination_type": "entity",
+          "destination_columns": [
+            "id",
+            "type"
+          ],
+          "prefix": "counterparty"
         },
         {
           "id": "33333333-3333-3333-3333-333333333333",
@@ -91,8 +108,7 @@
           "destination_type": "order",
           "destination_columns": [
             "id"
-          ],
-          "prefix": "lines"
+          ]
         }
       ],
       "types": [
@@ -713,14 +729,18 @@
             "created_by",
             "modified_at",
             "modified_by",
-            "archived"
+            "archived",
+            "counterparty_id",
+            "counterparty_type"
           ],
           "grouped_fields": {
             "order": [
               "id",
               "type",
               "total",
-              "customer_id"
+              "customer_id",
+              "counterparty_id",
+              "counterparty_type"
             ],
             "entity": [
               "id",
@@ -748,7 +768,9 @@
             "created_at": "timestamptz",
             "created_by": "uuid",
             "modified_at": "timestamptz",
-            "modified_by": "uuid"
+            "modified_by": "uuid",
+            "counterparty_id": "uuid",
+            "counterparty_type": "text"
           },
           "variations": [
             "order"

src/database/schema.rs

@@ -622,7 +622,23 @@ pub(crate) fn resolve_relation<'a>(
     }
   }
 
+  if !resolved {
+    // 1. If there's EXACTLY ONE relation with a null prefix, it's the base structural edge. Pick it.
+    let mut null_prefix_ids = Vec::new();
+    for (i, rel) in matching_rels.iter().enumerate() {
+      if rel.prefix.is_none() {
+        null_prefix_ids.push(i);
+      }
+    }
+    if null_prefix_ids.len() == 1 {
+      chosen_idx = null_prefix_ids[0];
+      resolved = true;
+    }
+  }
+
   if !resolved && relative_keys.is_some() {
+    // 2. M:M Disambiguation: The child schema will explicitly define an outbound property
+    // matching one of the relational prefixes (e.g. "target"). We use the OTHER one (e.g. "source").
     let keys = relative_keys.unwrap();
     let mut missing_prefix_ids = Vec::new();
     for (i, rel) in matching_rels.iter().enumerate() {
@@ -634,6 +650,7 @@ pub(crate) fn resolve_relation<'a>(
     }
     if missing_prefix_ids.len() == 1 {
       chosen_idx = missing_prefix_ids[0];
+      // resolved = true;
     }
   }
 

src/merger/mod.rs

@@ -508,7 +508,7 @@ impl Merger {
       );
 
       entity_fields = new_fields;
-    } else if changes.is_empty() {
+    } else if changes.is_empty() && replaces_id.is_none() {
       let mut new_fields = serde_json::Map::new();
       new_fields.insert(
         "id".to_string(),
@@ -524,6 +524,8 @@ impl Merger {
         .unwrap_or(false);
       entity_change_kind = if is_archived {
         Some("delete".to_string())
+      } else if changes.is_empty() && replaces_id.is_some() {
+        Some("replace".to_string())
       } else {
         Some("update".to_string())
       };
@@ -796,9 +798,9 @@ impl Merger {
 
     let mut old_vals = serde_json::Map::new();
     let mut new_vals = serde_json::Map::new();
-    let is_update = change_kind == "update" || change_kind == "delete";
+    let exists = change_kind == "update" || change_kind == "delete" || change_kind == "replace";
 
-    if !is_update {
+    if !exists {
       let system_keys = vec![
         "id".to_string(),
         "created_by".to_string(),
@@ -835,7 +837,7 @@ impl Merger {
     }
 
     let mut complete = entity_fields.clone();
-    if is_update {
+    if exists {
       if let Some(fetched) = entity_fetched {
         let mut temp = fetched.clone();
         for (k, v) in entity_fields {
@@ -865,7 +867,7 @@ impl Merger {
     }
 
     let mut notify_sql = None;
-    if type_obj.historical {
+    if type_obj.historical && change_kind != "replace" {
       let change_sql = format!(
         "INSERT INTO agreego.change (\"old\", \"new\", entity_id, id, kind, modified_at, modified_by) VALUES ({}, {}, {}, {}, {}, {}, {})",
         Self::quote_literal(&old_val_obj),

src/tests/fixtures.rs

@@ -8602,3 +8602,9 @@ fn test_merger_0_11() {
     let path = format!("{}/fixtures/merger.json", env!("CARGO_MANIFEST_DIR"));
     crate::tests::runner::run_test_case(&path, 0, 11).unwrap();
 }
+
+#[test]
+fn test_merger_0_12() {
+    let path = format!("{}/fixtures/merger.json", env!("CARGO_MANIFEST_DIR"));
+    crate::tests::runner::run_test_case(&path, 0, 12).unwrap();
+}

version

@@ -1 +1 @@
-1.0.95
+1.0.98