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Aggregations & GroupBy

EntityTS provides strongly-typed LINQ aggregate operators and multi-column grouping.

LINQ Aggregations​

Perform standard LINQ aggregations with compile-time lambda selectors:

// Count
const totalUsers = await db.users.count();
const activeAdmins = await db.users
  .where(u => u.role, '=', 'admin')
  .where(u => u.isActive, '=', true)
  .count();

// Sum, Avg, Min, Max
const totalRevenue = await db.orders.sum(o => o.totalAmount);
const avgAge = await db.users.avg(u => u.age);
const minPrice = await db.products.min(p => p.price);
const maxScore = await db.scores.max(s => s.score);

LINQ Group By & Projections​

Group records by key and project calculated aggregate metrics:

const stats = await db.orders
  .groupBy(o => o.status)
  .select((group, g) => ({
    status: g.status,
    orderCount: group.count(),
    totalRevenue: group.sum('totalAmount'),
    averageOrder: group.avg('totalAmount'),
  }))
  .toList();