diff --git a/.jules/bolt.md b/.jules/bolt.md
index f1a8c1466..2ec7bb9ca 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -77,3 +77,9 @@ Optimized metric route processing to O(N) by creating a mapping of routes direct
 ## 2024-07-13 - [Optimize Export Dictionary FK lookups]
 **Learning:** Found O(N * C * E) performance bottleneck in ERD export dictionaries due to repeated array searching with `edges.some()` inside a nested loop over nodes and columns.
 **Action:** Replace repeated linear array scans for edges by precomputing O(1) Set lookups of foreign key column handles per node before looping.
+## 2024-07-28 - Optimize ERD dangling edge lookups
+**Learning:** Checking for edge validity in ERD exporters by matching edge handle strings against all column arrays nested inside all graph nodes using `Array.some` or `Array.find` takes $O(N * C)$ time for every edge ($O(E * N * C)$). This causes lag on large schemas.
+**Action:** Since edge handles are hex-encoded strings representing the original column name, directly parsing the column name out of the edge handle allows for an $O(1)$ column lookup instead of iterating through nodes and re-encoding their column properties to find a match.
+## 2026-09-04 - Asynchronous Query Resolution in Test Suites
+**Learning:** Tests can fail unpredictably with a "TestingLibraryElementError: Unable to find an element" exception when synchronous queries like `getByText` or `getByRole` are used immediately after user interactions (e.g. `fireEvent.change`) that trigger asynchronous state updates. Even if the state appears to update immediately locally, it can fall victim to race conditions.
+**Action:** When validating visual changes tied to state updates dependent on async operations or complex renders (like diagram search results in ERDs), always use asynchronous queries (e.g., `await screen.findByText(...)`) instead of their synchronous equivalents (`screen.getByText(...)`).
diff --git a/frontend/src/App.coverage.test.tsx b/frontend/src/App.coverage.test.tsx
index 0b9a20aa8..78baff565 100644
--- a/frontend/src/App.coverage.test.tsx
+++ b/frontend/src/App.coverage.test.tsx
@@ -326,9 +326,9 @@ describe('App orchestration coverage', () => {
     fireEvent.click(screen.getAllByRole('button', { name: '열기' })[1]!)
     expect(screen.getByRole('heading', { name: '다이어그램' })).toBeInTheDocument()
     fireEvent.change(screen.getByLabelText('다이어그램 검색'), { target: { value: 'no-match' } })
-    expect(screen.getByText('검색 결과가 없습니다.')).toBeInTheDocument()
+    expect(await screen.findByText('검색 결과가 없습니다.')).toBeInTheDocument()
     fireEvent.change(screen.getByLabelText('다이어그램 검색'), { target: { value: 'failed' } })
-    expect(screen.getByText('ERD_all_2')).toBeInTheDocument()
+    expect(await screen.findByText('ERD_all_2')).toBeInTheDocument()
     fireEvent.click(screen.getByRole('button', { name: '편집기 열기' }))
     expect(screen.getByRole('toolbar', { name: 'ERD 캔버스 도구' })).toBeInTheDocument()
 
diff --git a/frontend/src/erd/__tests__/prisma.test.ts b/frontend/src/erd/__tests__/prisma.test.ts
index 73bca1a66..5570947fb 100644
--- a/frontend/src/erd/__tests__/prisma.test.ts
+++ b/frontend/src/erd/__tests__/prisma.test.ts
@@ -63,8 +63,8 @@ describe('exportPrisma', () => {
         id: 'e1',
         source: '2',
         target: '1',
-        sourceHandle: 'src-user_id',
-        targetHandle: 'tgt-id',
+        sourceHandle: 'src-c-0075-0073-0065-0072-005f-0069-0064',
+        targetHandle: 'tgt-c-0069-0064',
         label: 'users_posts',
       },
     ];
@@ -224,8 +224,8 @@ describe('exportPrisma', () => {
         id: 'e1',
         source: '2',
         target: '1',
-        sourceHandle: 'src-user_id',
-        targetHandle: 'tgt-id',
+        sourceHandle: 'src-c-0075-0073-0065-0072-005f-0069-0064',
+        targetHandle: 'tgt-c-0069-0064',
         label: '1to1',
       },
     ];
diff --git a/frontend/src/erd/export.ts b/frontend/src/erd/export.ts
index 62ce7219e..808bd85f7 100644
--- a/frontend/src/erd/export.ts
+++ b/frontend/src/erd/export.ts
@@ -2,7 +2,7 @@ import type { Node, Edge } from '@xyflow/react';
 import { normalizeBusinessGroupColor } from './businessGroups';
 import type { IndexRecommendation } from './cardinality';
 import type { ForeignKeyEdgeData, TableNodeData } from './convert';
-import { sourceColumnHandleId, targetColumnHandleId } from './handleUtils';
+import { parseColumnNameFromHandle } from './handleUtils';
 
 export * from './exportDataDictionary';
 
@@ -67,12 +67,22 @@ function fkColumnsForEdge(
     return { sourceColumns, targetColumns };
   }
 
-  const sourceHandleColumn = (sourceNode.data.columns || [])
-    .find((column) => sourceColumnHandleId(column.column_name) === edge.sourceHandle)
-    ?.column_name;
-  const targetHandleColumn = (targetNode.data.columns || [])
-    .find((column) => targetColumnHandleId(column.column_name) === edge.targetHandle)
-    ?.column_name;
+  let sourceHandleColumn: string | undefined = undefined;
+  if (edge.sourceHandle && edge.sourceHandle.startsWith('src-')) {
+    const parsedSource = parseColumnNameFromHandle(edge.sourceHandle.slice(4));
+    if (parsedSource && (sourceNode.data.columns || []).some(c => c.column_name === parsedSource)) {
+      sourceHandleColumn = parsedSource;
+    }
+  }
+
+  let targetHandleColumn: string | undefined = undefined;
+  if (edge.targetHandle && edge.targetHandle.startsWith('tgt-')) {
+    const parsedTarget = parseColumnNameFromHandle(edge.targetHandle.slice(4));
+    if (parsedTarget && (targetNode.data.columns || []).some(c => c.column_name === parsedTarget)) {
+      targetHandleColumn = parsedTarget;
+    }
+  }
+
   if (sourceHandleColumn && targetHandleColumn) {
     return { sourceColumns: [sourceHandleColumn], targetColumns: [targetHandleColumn] };
   }
diff --git a/frontend/src/erd/handleUtils.ts b/frontend/src/erd/handleUtils.ts
index 054d5ab2a..546f8a016 100644
--- a/frontend/src/erd/handleUtils.ts
+++ b/frontend/src/erd/handleUtils.ts
@@ -14,3 +14,9 @@ export function sourceColumnHandleId(columnName: string): string {
 export function targetColumnHandleId(columnName: string): string {
   return `tgt-${sanitizeHandleId(columnName)}`
 }
+
+export function parseColumnNameFromHandle(handleId: string): string {
+  if (!handleId || handleId === 'c-empty' || !handleId.startsWith('c-')) return '';
+  const parts = handleId.slice(2).split('-');
+  return parts.map(p => String.fromCodePoint(parseInt(p, 16))).join('');
+}
diff --git a/frontend/src/erd/prisma.ts b/frontend/src/erd/prisma.ts
index 211dfdd8d..589641a0d 100644
--- a/frontend/src/erd/prisma.ts
+++ b/frontend/src/erd/prisma.ts
@@ -1,6 +1,6 @@
 import type { Node, Edge } from "@xyflow/react";
 import type { TableNodeData } from "./convert";
-import { sanitizeHandleId } from "./handleUtils";
+import { sanitizeHandleId, parseColumnNameFromHandle } from "./handleUtils";
 
 function sanitizeName(name: string): string {
   // Prisma model and field names must start with a letter and contain only alphanumeric characters and underscores
@@ -69,20 +69,29 @@ export function exportPrisma(
     const relName = sanitizeName(String(edge.label || `${sourceNode.data.title}_${targetNode.data.title}`));
 
     let sourceField = "";
-    if (edge.sourceHandle?.startsWith("src-")) {
-      sourceField = edge.sourceHandle.slice(4);
+    if (edge.sourceHandle && edge.sourceHandle.startsWith("src-")) {
+      const parsedSource = parseColumnNameFromHandle(edge.sourceHandle.slice(4));
+      if (parsedSource && (sourceNode.data.columns || []).some(c => c.column_name === parsedSource)) {
+        sourceField = parsedSource;
+      }
+    }
+
+    if (sourceField) {
       fkNodeColumnPairs.add(`${edge.source}:${sourceField}`);
     } else if (!edge.sourceHandle) {
       fkNodesWithoutHandles.add(edge.source);
     }
 
     let targetField = "id"; // fallback
-    if (edge.targetHandle?.startsWith("tgt-")) {
-      targetField = edge.targetHandle.slice(4);
+    if (edge.targetHandle && edge.targetHandle.startsWith("tgt-")) {
+      const parsedTarget = parseColumnNameFromHandle(edge.targetHandle.slice(4));
+      if (parsedTarget && (targetNode.data.columns || []).some(c => c.column_name === parsedTarget)) {
+        targetField = parsedTarget;
+      }
     }
 
     if (sourceField) {
-      const isUnique = sourceNode.data.columns.find(c => c.column_name === sourceField)?.is_pk || false;
+      const isUnique = sourceNode.data.columns.some(c => c.column_name === sourceField && c.is_pk);
 
       const relList = incomingRelationsByNode.get(edge.target) || [];
       relList.push({
diff --git a/plan.md b/plan.md
new file mode 100644
index 000000000..f5c39a933
--- /dev/null
+++ b/plan.md
@@ -0,0 +1,3 @@
+1. **Fix Flaky Test in `frontend/src/App.coverage.test.tsx`**: Update the failing test `navigates dashboard, project, and diagram states including empty/search branches` to use asynchronous queries (`findByText`, `findAllByText`, `findByRole`) when checking for elements that render based on asynchronous state updates or API mocks. According to the `.jules/bolt.md` (or general memory) and the traceback, we need to use `await screen.findByText('검색 결과가 없습니다.')` instead of `screen.getByText` because filtering depends on state changes that may not have painted immediately after the user interaction. The test is failing due to a race condition (TestingLibraryElementError: Unable to find an element with the text...).
+2. **Run Frontend checks**: `cd frontend && pnpm run typecheck && pnpm test -- --run` to verify the fix works.
+3. **Complete pre-commit steps**: Complete pre-commit steps to ensure proper testing, verification, review, and reflection are done.