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skills/optimizing-query-selection/references/nested-selection.md

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+# Nested Selection Patterns
+
+## Deep Relation Hierarchies
+
+Select fields deep in relation hierarchies:
+
+```typescript
+const posts = await prisma.post.findMany({
+  select: {
+    title: true,
+    author: {
+      select: {
+        name: true,
+        profile: {
+          select: {
+            avatar: true,
+          },
+        },
+      },
+    },
+    comments: {
+      select: {
+        content: true,
+        author: {
+          select: {
+            name: true,
+          },
+        },
+      },
+      take: 5,
+      orderBy: {
+        createdAt: 'desc',
+      },
+    },
+  },
+})
+```
+
+## Combining Select with Filtering
+
+Optimize both data transfer and query performance:
+
+```typescript
+const recentPosts = await prisma.post.findMany({
+  where: {
+    published: true,
+    createdAt: {
+      gte: new Date(Date.now() - 7 * 24 * 60 * 60 * 1000),
+    },
+  },
+  select: {
+    id: true,
+    title: true,
+    excerpt: true,
+    createdAt: true,
+    author: {
+      select: {
+        id: true,
+        name: true,
+      },
+    },
+    _count: {
+      select: {
+        comments: true,
+        likes: true,
+      },
+    },
+  },
+  orderBy: {
+    createdAt: 'desc',
+  },
+  take: 10,
+})
+```
+
+## Key Principles
+
+- Nest selections to match data shape requirements
+- Use `take` on nested relations to prevent over-fetching
+- Combine `orderBy` with nested relations for sorted results
+- Use `_count` for relation counts instead of loading all records