diff --git a/openspec/changes/user-accounts/tasks.md b/openspec/changes/user-accounts/tasks.md
index de7466d..740d6cb 100644
--- a/openspec/changes/user-accounts/tasks.md
+++ b/openspec/changes/user-accounts/tasks.md
@@ -38,7 +38,7 @@
 ## 7. Update Existing API Routes
 
 - [x] 7.1 `[sonnet]` Add `getAuthUser()` check to all data API routes: `/api/upload`, `/api/candles`, `/api/charts`, `/api/annotations`, `/api/annotation-types`, `/api/span-annotations`, `/api/span-label-types`, `/api/export`
-- [ ] 7.2 `[opus]` Update all Drizzle queries to filter by `user_id` from authenticated session (SELECT, INSERT, DELETE)
+- [x] 7.2 `[opus]` Update all Drizzle queries to filter by `user_id` from authenticated session (SELECT, INSERT, DELETE)
 - [ ] 7.3 `[sonnet]` Add `getAuthUser()` check to all proxy API routes: `/api/predict`, `/api/predict/batch`, `/api/model/info`, `/api/model/load`, `/api/patterns/detect`, `/api/patterns/available`, `/api/training/start`, `/api/training/runs`
 - [ ] 7.4 `[haiku]` Add `X-User-ID` header to all fetch calls from proxy routes to the FastAPI ML service
 
diff --git a/src/app/api/annotation-types/[id]/route.ts b/src/app/api/annotation-types/[id]/route.ts
index f40524c..019d518 100644
--- a/src/app/api/annotation-types/[id]/route.ts
+++ b/src/app/api/annotation-types/[id]/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { annotationTypes } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 type RouteContext = {
@@ -51,7 +51,7 @@ export async function PATCH(
     const result = await db
       .update(annotationTypes)
       .set(updateData)
-      .where(eq(annotationTypes.id, idNum))
+      .where(and(eq(annotationTypes.id, idNum), eq(annotationTypes.user_id, user.id)))
       .returning();
 
     if (result.length === 0) {
diff --git a/src/app/api/annotation-types/route.ts b/src/app/api/annotation-types/route.ts
index 396391e..f18716a 100644
--- a/src/app/api/annotation-types/route.ts
+++ b/src/app/api/annotation-types/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { annotationTypes, annotations } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 // GET - List all annotation types
@@ -12,7 +12,7 @@ export async function GET() {
   }
 
   try {
-    const types = await db.select().from(annotationTypes);
+    const types = await db.select().from(annotationTypes).where(eq(annotationTypes.user_id, user.id));
     return NextResponse.json(types);
   } catch (error) {
     console.error('Error fetching annotation types:', error);
@@ -35,8 +35,8 @@ export async function POST(request: NextRequest) {
 
     // Special case: seed default types
     if (body.action === 'seed') {
-      const existing = await db.select().from(annotationTypes);
-      
+      const existing = await db.select().from(annotationTypes).where(eq(annotationTypes.user_id, user.id));
+
       if (existing.length > 0) {
         return NextResponse.json({ message: 'Types already seeded' });
       }
@@ -49,6 +49,7 @@ export async function POST(request: NextRequest) {
           category: 'marker',
           icon: 'arrowUp',
           is_active: true,
+          user_id: user.id,
         },
         {
           name: 'break_down',
@@ -57,6 +58,7 @@ export async function POST(request: NextRequest) {
           category: 'marker',
           icon: 'arrowDown',
           is_active: true,
+          user_id: user.id,
         },
         {
           name: 'line',
@@ -65,6 +67,7 @@ export async function POST(request: NextRequest) {
           category: 'line',
           icon: 'line',
           is_active: true,
+          user_id: user.id,
         },
       ];
 
@@ -91,6 +94,7 @@ export async function POST(request: NextRequest) {
         category,
         icon: icon || null,
         is_active: true,
+        user_id: user.id,
       })
       .returning();
 
@@ -130,11 +134,11 @@ export async function DELETE(request: NextRequest) {
       );
     }
 
-    // Check if the type exists
+    // Check if the type exists and belongs to user
     const type = await db
       .select()
       .from(annotationTypes)
-      .where(eq(annotationTypes.id, parseInt(id)))
+      .where(and(eq(annotationTypes.id, parseInt(id)), eq(annotationTypes.user_id, user.id)))
       .limit(1);
 
     if (type.length === 0) {
@@ -144,11 +148,11 @@ export async function DELETE(request: NextRequest) {
       );
     }
 
-    // Check if any annotations use this type
+    // Check if any of this user's annotations use this type
     const existingAnnotations = await db
       .select()
       .from(annotations)
-      .where(eq(annotations.label_type, type[0].name))
+      .where(and(eq(annotations.label_type, type[0].name), eq(annotations.user_id, user.id)))
       .limit(1);
 
     if (existingAnnotations.length > 0) {
@@ -158,7 +162,7 @@ export async function DELETE(request: NextRequest) {
       );
     }
 
-    await db.delete(annotationTypes).where(eq(annotationTypes.id, parseInt(id)));
+    await db.delete(annotationTypes).where(and(eq(annotationTypes.id, parseInt(id)), eq(annotationTypes.user_id, user.id)));
 
     return NextResponse.json({ message: 'Annotation type deleted successfully' });
   } catch (error) {
diff --git a/src/app/api/annotations/[id]/route.ts b/src/app/api/annotations/[id]/route.ts
index 5db144b..0f74ddc 100644
--- a/src/app/api/annotations/[id]/route.ts
+++ b/src/app/api/annotations/[id]/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { annotations } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 export async function PATCH(
@@ -37,7 +37,7 @@ export async function PATCH(
     const result = await db
       .update(annotations)
       .set({ geometry })
-      .where(eq(annotations.id, id))
+      .where(and(eq(annotations.id, id), eq(annotations.user_id, user.id)))
       .returning();
 
     if (result.length === 0) {
@@ -79,7 +79,7 @@ export async function DELETE(
 
     const result = await db
       .delete(annotations)
-      .where(eq(annotations.id, id))
+      .where(and(eq(annotations.id, id), eq(annotations.user_id, user.id)))
       .returning();
 
     if (result.length === 0) {
diff --git a/src/app/api/annotations/route.ts b/src/app/api/annotations/route.ts
index 514abc7..85bc978 100644
--- a/src/app/api/annotations/route.ts
+++ b/src/app/api/annotations/route.ts
@@ -17,7 +17,7 @@ export async function GET(request: NextRequest) {
 
     // Fall back to most recent chart if no chartId provided
     if (!chartId) {
-      const latest = await db.select({ id: charts.id }).from(charts).orderBy(desc(charts.created_at)).limit(1);
+      const latest = await db.select({ id: charts.id }).from(charts).where(eq(charts.user_id, user.id)).orderBy(desc(charts.created_at)).limit(1);
       if (latest.length === 0) {
         return NextResponse.json([]);
       }
@@ -35,7 +35,7 @@ export async function GET(request: NextRequest) {
     const allAnnotations = await db
       .select()
       .from(annotations)
-      .where(eq(annotations.chart_id, chartIdNum));
+      .where(and(eq(annotations.chart_id, chartIdNum), eq(annotations.user_id, user.id)));
 
     const normalized = allAnnotations.map((a) => ({
       ...a,
@@ -71,8 +71,8 @@ export async function POST(request: NextRequest) {
       );
     }
 
-    // Verify chart exists
-    const chartExists = await db.select({ id: charts.id }).from(charts).where(eq(charts.id, chart_id)).limit(1);
+    // Verify chart exists and belongs to user
+    const chartExists = await db.select({ id: charts.id }).from(charts).where(and(eq(charts.id, chart_id), eq(charts.user_id, user.id))).limit(1);
     if (chartExists.length === 0) {
       return NextResponse.json(
         { error: 'Chart not found' },
@@ -89,6 +89,7 @@ export async function POST(request: NextRequest) {
       .insert(annotations)
       .values({
         chart_id,
+        user_id: user.id,
         timestamp: timestampDate,
         label_type,
         geometry: geometry || null,
@@ -139,7 +140,7 @@ export async function DELETE(request: NextRequest) {
           { status: 400 }
         );
       }
-      result = await db.delete(annotations).where(eq(annotations.chart_id, chartIdNum)).returning();
+      result = await db.delete(annotations).where(and(eq(annotations.chart_id, chartIdNum), eq(annotations.user_id, user.id))).returning();
     } else if (type) {
       const types = type.split(',').map((t) => t.trim());
       if (chartId) {
@@ -152,12 +153,12 @@ export async function DELETE(request: NextRequest) {
         }
         result = await db
           .delete(annotations)
-          .where(and(inArray(annotations.label_type, types), eq(annotations.chart_id, chartIdNum)))
+          .where(and(inArray(annotations.label_type, types), eq(annotations.chart_id, chartIdNum), eq(annotations.user_id, user.id)))
           .returning();
       } else {
         result = await db
           .delete(annotations)
-          .where(inArray(annotations.label_type, types))
+          .where(and(inArray(annotations.label_type, types), eq(annotations.user_id, user.id)))
           .returning();
       }
     } else {
diff --git a/src/app/api/candles/route.ts b/src/app/api/candles/route.ts
index 34be8b0..533ffeb 100644
--- a/src/app/api/candles/route.ts
+++ b/src/app/api/candles/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { candles, charts } from '@/lib/db/schema';
-import { asc, desc, eq } from 'drizzle-orm';
+import { asc, desc, eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 export async function GET(request: NextRequest) {
@@ -16,7 +16,7 @@ export async function GET(request: NextRequest) {
 
     // Fall back to most recent chart if no chartId provided
     if (!chartId) {
-      const latest = await db.select({ id: charts.id }).from(charts).orderBy(desc(charts.created_at)).limit(1);
+      const latest = await db.select({ id: charts.id }).from(charts).where(eq(charts.user_id, user.id)).orderBy(desc(charts.created_at)).limit(1);
       if (latest.length === 0) {
         return NextResponse.json([]);
       }
@@ -31,6 +31,12 @@ export async function GET(request: NextRequest) {
       );
     }
 
+    // Verify chart belongs to user
+    const chartOwner = await db.select({ id: charts.id }).from(charts).where(and(eq(charts.id, chartIdNum), eq(charts.user_id, user.id))).limit(1);
+    if (chartOwner.length === 0) {
+      return NextResponse.json({ error: 'Chart not found' }, { status: 404 });
+    }
+
     const allCandles = await db
       .select({
         time: candles.time,
diff --git a/src/app/api/charts/[id]/route.ts b/src/app/api/charts/[id]/route.ts
index 8e24982..109bac6 100644
--- a/src/app/api/charts/[id]/route.ts
+++ b/src/app/api/charts/[id]/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { charts, candles, annotations, spanAnnotations } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 export async function GET(
@@ -20,7 +20,7 @@ export async function GET(
     return NextResponse.json({ error: 'Invalid chart ID' }, { status: 400 });
   }
 
-  const result = await db.select().from(charts).where(eq(charts.id, chartId)).limit(1);
+  const result = await db.select().from(charts).where(and(eq(charts.id, chartId), eq(charts.user_id, user.id))).limit(1);
   
   if (result.length === 0) {
     return NextResponse.json({ error: 'Chart not found' }, { status: 404 });
@@ -45,7 +45,7 @@ export async function DELETE(
     return NextResponse.json({ error: 'Invalid chart ID' }, { status: 400 });
   }
 
-  const existing = await db.select().from(charts).where(eq(charts.id, chartId)).limit(1);
+  const existing = await db.select().from(charts).where(and(eq(charts.id, chartId), eq(charts.user_id, user.id))).limit(1);
   if (existing.length === 0) {
     return NextResponse.json({ error: 'Chart not found' }, { status: 404 });
   }
diff --git a/src/app/api/charts/route.ts b/src/app/api/charts/route.ts
index 65bed5d..136daf5 100644
--- a/src/app/api/charts/route.ts
+++ b/src/app/api/charts/route.ts
@@ -1,7 +1,7 @@
 import { NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { charts } from '@/lib/db/schema';
-import { desc } from 'drizzle-orm';
+import { desc, eq } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 export async function GET() {
@@ -10,6 +10,6 @@ export async function GET() {
     return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
   }
 
-  const allCharts = await db.select().from(charts).orderBy(desc(charts.created_at));
+  const allCharts = await db.select().from(charts).where(eq(charts.user_id, user.id)).orderBy(desc(charts.created_at));
   return NextResponse.json(allCharts);
 }
diff --git a/src/app/api/export/route.ts b/src/app/api/export/route.ts
index d00387c..e7ad1da 100644
--- a/src/app/api/export/route.ts
+++ b/src/app/api/export/route.ts
@@ -23,7 +23,7 @@ export async function GET(request: NextRequest) {
 
     // Fall back to most recent chart if no chartId provided
     if (!chartId) {
-      const latest = await db.select({ id: charts.id }).from(charts).orderBy(desc(charts.created_at)).limit(1);
+      const latest = await db.select({ id: charts.id }).from(charts).where(eq(charts.user_id, user.id)).orderBy(desc(charts.created_at)).limit(1);
       if (latest.length === 0) {
         return new NextResponse('timestamp,label_type,price\n', {
           headers: {
@@ -46,7 +46,7 @@ export async function GET(request: NextRequest) {
     const allAnnotations = await db
       .select()
       .from(annotations)
-      .where(eq(annotations.chart_id, chartIdNum));
+      .where(and(eq(annotations.chart_id, chartIdNum), eq(annotations.user_id, user.id)));
 
     // Build CSV content
     const csvRows = ['timestamp,label_type,price'];
diff --git a/src/app/api/span-annotations/[id]/route.ts b/src/app/api/span-annotations/[id]/route.ts
index e77201a..a4a7d25 100644
--- a/src/app/api/span-annotations/[id]/route.ts
+++ b/src/app/api/span-annotations/[id]/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { spanAnnotations } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 // PATCH - Update span annotation
@@ -29,11 +29,11 @@ export async function PATCH(
 
     const { label, confidence, outcome, notes, sub_spans } = body;
 
-    // Check if the span exists
+    // Check if the span exists and belongs to user
     const existing = await db
       .select()
       .from(spanAnnotations)
-      .where(eq(spanAnnotations.id, idNum))
+      .where(and(eq(spanAnnotations.id, idNum), eq(spanAnnotations.user_id, user.id)))
       .limit(1);
 
     if (existing.length === 0) {
@@ -54,7 +54,7 @@ export async function PATCH(
     const result = await db
       .update(spanAnnotations)
       .set(updates)
-      .where(eq(spanAnnotations.id, idNum))
+      .where(and(eq(spanAnnotations.id, idNum), eq(spanAnnotations.user_id, user.id)))
       .returning();
 
     const s = result[0];
@@ -94,11 +94,11 @@ export async function DELETE(
       );
     }
 
-    // Check if the span exists
+    // Check if the span exists and belongs to user
     const existing = await db
       .select()
       .from(spanAnnotations)
-      .where(eq(spanAnnotations.id, idNum))
+      .where(and(eq(spanAnnotations.id, idNum), eq(spanAnnotations.user_id, user.id)))
       .limit(1);
 
     if (existing.length === 0) {
@@ -108,7 +108,7 @@ export async function DELETE(
       );
     }
 
-    await db.delete(spanAnnotations).where(eq(spanAnnotations.id, idNum));
+    await db.delete(spanAnnotations).where(and(eq(spanAnnotations.id, idNum), eq(spanAnnotations.user_id, user.id)));
 
     return NextResponse.json({ message: 'Span annotation deleted successfully' });
   } catch (error) {
diff --git a/src/app/api/span-annotations/export/route.ts b/src/app/api/span-annotations/export/route.ts
index 2b6b5ae..3524169 100644
--- a/src/app/api/span-annotations/export/route.ts
+++ b/src/app/api/span-annotations/export/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { spanAnnotations, charts } from '@/lib/db/schema';
-import { eq, desc } from 'drizzle-orm';
+import { eq, desc, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 function sanitizeCsvCell(value: string): string {
@@ -53,6 +53,7 @@ export async function GET(request: NextRequest) {
       const latest = await db
         .select({ id: charts.id })
         .from(charts)
+        .where(eq(charts.user_id, user.id))
         .orderBy(desc(charts.created_at))
         .limit(1);
       
@@ -78,7 +79,7 @@ export async function GET(request: NextRequest) {
     const spans = await db
       .select()
       .from(spanAnnotations)
-      .where(eq(spanAnnotations.chart_id, chartIdNum))
+      .where(and(eq(spanAnnotations.chart_id, chartIdNum), eq(spanAnnotations.user_id, user.id)))
       .orderBy(spanAnnotations.start_time);
 
     if (format === 'json') {
diff --git a/src/app/api/span-annotations/route.ts b/src/app/api/span-annotations/route.ts
index 2faf191..8ca2b4d 100644
--- a/src/app/api/span-annotations/route.ts
+++ b/src/app/api/span-annotations/route.ts
@@ -33,7 +33,7 @@ export async function GET(request: NextRequest) {
     const spans = await db
       .select()
       .from(spanAnnotations)
-      .where(eq(spanAnnotations.chart_id, chartIdNum))
+      .where(and(eq(spanAnnotations.chart_id, chartIdNum), eq(spanAnnotations.user_id, user.id)))
       .orderBy(desc(spanAnnotations.start_time));
 
     const normalized = spans.map((s) => ({
@@ -91,6 +91,7 @@ export async function POST(request: NextRequest) {
       .insert(spanAnnotations)
       .values({
         chart_id,
+        user_id: user.id,
         start_time: new Date(actualStartTime * 1000),
         end_time: new Date(actualEndTime * 1000),
         label,
@@ -148,8 +149,8 @@ export async function DELETE(request: NextRequest) {
       );
     }
 
-    // Build filter conditions
-    const conditions = [eq(spanAnnotations.chart_id, chartIdInt)];
+    // Build filter conditions (always scoped to user)
+    const conditions = [eq(spanAnnotations.chart_id, chartIdInt), eq(spanAnnotations.user_id, user.id)];
     if (source) conditions.push(eq(spanAnnotations.source, source));
     if (label) conditions.push(eq(spanAnnotations.label, label));
 
diff --git a/src/app/api/span-label-types/[id]/route.ts b/src/app/api/span-label-types/[id]/route.ts
index 2f1bd78..023e749 100644
--- a/src/app/api/span-label-types/[id]/route.ts
+++ b/src/app/api/span-label-types/[id]/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { spanLabelTypes, spanAnnotations } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 // PATCH - Update span label type
@@ -29,11 +29,11 @@ export async function PATCH(
 
     const { name, display_name, color, hotkey, is_active, sort_order } = body;
 
-    // Check if the type exists
+    // Check if the type exists and belongs to user
     const existing = await db
       .select()
       .from(spanLabelTypes)
-      .where(eq(spanLabelTypes.id, idNum))
+      .where(and(eq(spanLabelTypes.id, idNum), eq(spanLabelTypes.user_id, user.id)))
       .limit(1);
 
     if (existing.length === 0) {
@@ -55,7 +55,7 @@ export async function PATCH(
     const result = await db
       .update(spanLabelTypes)
       .set(updates)
-      .where(eq(spanLabelTypes.id, idNum))
+      .where(and(eq(spanLabelTypes.id, idNum), eq(spanLabelTypes.user_id, user.id)))
       .returning();
 
     return NextResponse.json(result[0]);
@@ -97,11 +97,11 @@ export async function DELETE(
       );
     }
 
-    // Check if the type exists
+    // Check if the type exists and belongs to user
     const type = await db
       .select()
       .from(spanLabelTypes)
-      .where(eq(spanLabelTypes.id, idNum))
+      .where(and(eq(spanLabelTypes.id, idNum), eq(spanLabelTypes.user_id, user.id)))
       .limit(1);
 
     if (type.length === 0) {
@@ -111,11 +111,11 @@ export async function DELETE(
       );
     }
 
-    // Check if any span annotations use this label
+    // Check if any of this user's span annotations use this label
     const existingSpans = await db
       .select()
       .from(spanAnnotations)
-      .where(eq(spanAnnotations.label, type[0].name))
+      .where(and(eq(spanAnnotations.label, type[0].name), eq(spanAnnotations.user_id, user.id)))
       .limit(1);
 
     if (existingSpans.length > 0) {
@@ -125,7 +125,7 @@ export async function DELETE(
       );
     }
 
-    await db.delete(spanLabelTypes).where(eq(spanLabelTypes.id, idNum));
+    await db.delete(spanLabelTypes).where(and(eq(spanLabelTypes.id, idNum), eq(spanLabelTypes.user_id, user.id)));
 
     return NextResponse.json({ message: 'Span label type deleted successfully' });
   } catch (error) {
diff --git a/src/app/api/span-label-types/route.ts b/src/app/api/span-label-types/route.ts
index 96b9483..0c73616 100644
--- a/src/app/api/span-label-types/route.ts
+++ b/src/app/api/span-label-types/route.ts
@@ -1,7 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { db } from '@/lib/db';
 import { spanLabelTypes } from '@/lib/db/schema';
-import { eq } from 'drizzle-orm';
+import { eq, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
 // GET - List all span label types (active only, sorted by sort_order)
@@ -15,7 +15,7 @@ export async function GET() {
     const types = await db
       .select()
       .from(spanLabelTypes)
-      .where(eq(spanLabelTypes.is_active, true))
+      .where(and(eq(spanLabelTypes.is_active, true), eq(spanLabelTypes.user_id, user.id)))
       .orderBy(spanLabelTypes.sort_order);
     
     return NextResponse.json(types);
@@ -55,6 +55,7 @@ export async function POST(request: NextRequest) {
         hotkey: hotkey || null,
         is_active: true,
         sort_order: sort_order ?? 0,
+        user_id: user.id,
       })
       .returning();
 
diff --git a/src/app/api/upload/route.ts b/src/app/api/upload/route.ts
index 4990fde..a452b92 100644
--- a/src/app/api/upload/route.ts
+++ b/src/app/api/upload/route.ts
@@ -2,17 +2,17 @@ import { NextRequest, NextResponse } from 'next/server';
 import Papa from 'papaparse';
 import { db } from '@/lib/db';
 import { candles, charts } from '@/lib/db/schema';
-import { eq, like } from 'drizzle-orm';
+import { eq, like, and } from 'drizzle-orm';
 import { getAuthUser } from '@/lib/auth';
 
-async function getUniqueChartName(baseName: string): Promise<string> {
-  // Check if the base name is already taken
-  const existing = await db.select().from(charts).where(eq(charts.name, baseName)).limit(1);
+async function getUniqueChartName(baseName: string, userId: string): Promise<string> {
+  // Check if the base name is already taken for this user
+  const existing = await db.select().from(charts).where(and(eq(charts.user_id, userId), eq(charts.name, baseName))).limit(1);
   if (existing.length === 0) return baseName;
 
   // Find existing charts with this base name pattern (e.g., "btc-daily-2", "btc-daily-3")
   const pattern = `${baseName}-%`;
-  const suffixed = await db.select({ name: charts.name }).from(charts).where(like(charts.name, pattern));
+  const suffixed = await db.select({ name: charts.name }).from(charts).where(and(eq(charts.user_id, userId), like(charts.name, pattern)));
 
   let maxSuffix = 1;
   for (const row of suffixed) {
@@ -124,11 +124,12 @@ export async function POST(request: NextRequest): Promise<NextResponse> {
             }
 
             // Get unique chart name (handle duplicates)
-            const chartName = await getUniqueChartName(baseName);
+            const chartName = await getUniqueChartName(baseName, user.id);
 
             // Create the chart
             const [newChart] = await db.insert(charts).values({
               name: chartName,
+              user_id: user.id,
             }).returning();
 
             // Parse and prepare candle data