From 635273f782ae2fdcac694dabb6732c9903fd4e27 Mon Sep 17 00:00:00 2001
From: PThorpe92 <preston@turso.tech>
Date: Fri, 19 Sep 2025 22:33:51 -0400
Subject: [PATCH] Prevent using a partial index as a scan driver

---
 core/translate/optimizer/constraints.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/core/translate/optimizer/constraints.rs b/core/translate/optimizer/constraints.rs
index cdd830b5f..049408b17 100644
--- a/core/translate/optimizer/constraints.rs
+++ b/core/translate/optimizer/constraints.rs
@@ -361,6 +361,15 @@ pub fn constraints_from_where_clause(
                 candidate.refs.truncate(first_inequality + 1);
             }
         }
+        cs.candidates.retain(|c| {
+            if let Some(idx) = &c.index {
+                if idx.where_clause.is_some() && c.refs.is_empty() {
+                    // prevent a partial index from even being considered as a scan driver.
+                    return false;
+                }
+            }
+            true
+        });
         constraints.push(cs);
     }