diff --git a/src/queryer/compiler.rs b/src/queryer/compiler.rs
index 1dc919e..642f5a6 100644
--- a/src/queryer/compiler.rs
+++ b/src/queryer/compiler.rs
@@ -496,6 +496,7 @@ impl<'a> Compiler<'a> {
     }
 
     self.compile_filter_conditions(r#type, type_aliases, &node, &base_alias, &mut where_clauses);
+    self.compile_polymorphic_bounds(r#type, type_aliases, &node, &mut where_clauses);
     self.compile_relation_conditions(
       r#type,
       type_aliases,
@@ -507,6 +508,54 @@ impl<'a> Compiler<'a> {
     Ok(where_clauses)
   }
 
+  fn compile_polymorphic_bounds(
+    &self,
+    _type: &crate::database::r#type::Type,
+    type_aliases: &std::collections::HashMap<String, String>,
+    node: &Node,
+    where_clauses: &mut Vec<String>,
+  ) {
+    if let Some(edges) = node.schema.obj.compiled_edges.get() {
+      if let Some(props) = node.schema.obj.compiled_properties.get() {
+        for (prop_name, edge) in edges {
+          if let Some(prop_schema) = props.get(prop_name) {
+            // Determine if the property schema resolves to a physical Database Entity
+            let mut bound_type_name = None;
+            if let Some(family_target) = prop_schema.obj.family.as_ref() {
+              bound_type_name = Some(family_target.split('.').next_back().unwrap_or(family_target).to_string());
+            } else if let Some(lookup_key) = prop_schema.obj.id.as_ref().or(prop_schema.obj.r#ref.as_ref()) {
+              bound_type_name = Some(lookup_key.split('.').next_back().unwrap_or(lookup_key).to_string());
+            }
+
+            if let Some(type_name) = bound_type_name {
+              // Ensure this type actually exists
+              if self.db.types.contains_key(&type_name) {
+                if let Some(relation) = self.db.relations.get(&edge.constraint) {
+                  let mut poly_col = None;
+                  let mut table_to_alias = "";
+
+                  if edge.forward && relation.source_columns.len() > 1 {
+                    poly_col = Some(&relation.source_columns[1]); // e.g., target_type
+                    table_to_alias = &relation.source_type; // e.g., relationship
+                  } else if !edge.forward && relation.destination_columns.len() > 1 {
+                    poly_col = Some(&relation.destination_columns[1]); // e.g., source_type
+                    table_to_alias = &relation.destination_type; // e.g., relationship
+                  }
+
+                  if let Some(col) = poly_col {
+                    if let Some(alias) = type_aliases.get(table_to_alias).or_else(|| type_aliases.get(&node.parent_alias)) {
+                      where_clauses.push(format!("{}.{} = '{}'", alias, col, type_name));
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+
   fn resolve_filter_alias(
     r#type: &crate::database::r#type::Type,
     type_aliases: &std::collections::HashMap<String, String>,