fix(sqlserver): avoid false unknown column diagnostics

apps/desktop/src/components/editor/QueryEditor.vue

@@ -393,6 +393,7 @@ async function ensureColumnsForTable(table: { name: string; schema?: string | nu
     table.name,
     table.schema ?? undefined,
   );
+  if (columns.length === 0) return;
   cachedColumnsByTable.set(cacheKey, columns);
 }
 
@@ -754,10 +755,12 @@ async function provideSqlCompletions(
           completionContext.insertSchema,
         );
         if (epoch !== completionEpoch) return null;
-        const insertKey = completionContext.insertSchema
-          ? `${completionContext.insertSchema}.${completionContext.insertTable}`
-          : completionContext.insertTable;
-        insertColumnsByTable.set(insertKey, insertCols);
+        if (insertCols.length > 0) {
+          const insertKey = completionContext.insertSchema
+            ? `${completionContext.insertSchema}.${completionContext.insertTable}`
+            : completionContext.insertTable;
+          insertColumnsByTable.set(insertKey, insertCols);
+        }
       } catch {
         // ignore
       }
@@ -865,6 +868,7 @@ async function provideSqlCompletions(
             refTable.schema,
           );
           if (epoch !== completionEpoch) return;
+          if (columns.length === 0) return;
           cachedColumnsByTable.set(cacheKey, columns);
         } catch (e) {
           console.error(`[DBX] Failed to load columns for ${cacheKey}:`, e);

apps/desktop/src/lib/sqlSemanticDiagnostics.ts

@@ -119,7 +119,9 @@ function columnsForTable(
   const keys = table.schema ? [`${table.schema}.${table.name}`, table.name] : [table.name];
   for (const key of keys) {
     const columns = columnsByTable.get(key) ?? columnsByTable.get(normalizeName(key));
-    if (columns) return columns;
+    // Empty metadata usually means the upstream schema lookup was inconclusive,
+    // so avoid surfacing a false "unknown column" warning.
+    if (columns && columns.length > 0) return columns;
   }
   return null;
 }

apps/desktop/src/stores/connectionStore.ts

@@ -1419,6 +1419,9 @@ export const useConnectionStore = defineStore("connection", () => {
     table: string,
     schema?: string,
   ): Promise<SqlCompletionColumn[]> {
+    if (isSchemaAwareDatabase(connectionId) && !schema) {
+      return [];
+    }
     const cacheKey = `${connectionId}:${database}:${schema || ""}:${table}`;
     if (!completionColumnsCache.value[cacheKey]) {
       await ensureConnected(connectionId);