When will you use this?

Use this lesson to build something you can demo — a sales dashboard or product search API.

• ShopNest.Analytics capstone proves you can filter, join, group, and paginate like a production reporting system.
• One complete analytics project on your resume beats reading fifty isolated LINQ operators.

Real-world: ERP inventory module

Real product: ERP inventory module (Manufacturing). operations team rely on purchase orders joined to suppliers every day. On this product, developers use ShopNest.Analytics Enterprise Platform to ship the full capstone — search, dashboards, EF Core, tests. Without it, the team would write longer loops, ship slower features, or pull too much data from SQL Server. The example below is simplified on purpose — production code adds error handling, logging, and tests around the same LINQ pattern.

Production-style code

// Solution layout (portfolio README)
ShopNest.Analytics/
  ShopNest.Domain/          — Product, Order, Customer entities
  ShopNest.Infrastructure/  — ShopDbContext, migrations
  ShopNest.Analytics.Api/   — SearchController, ReportsController
  ShopNest.Analytics.Core/  — DTOs, IAnalyticsService, validators
  ShopNest.Tests/           — LINQ unit tests with in-memory data

// Checklist before demo:
// ✓ Search API with optional filters + pagination
// ✓ Region revenue report (GroupBy + Sum)
// ✓ SQL logged in Development only
// ✓ AsNoTracking on all read endpoints
// ✓ One xUnit test per core query

What happens in production: In ERP inventory module, getting ShopNest.Analytics Enterprise Platform right means operations team see correct purchase orders joined to suppliers quickly. That is the difference between a tutorial snippet and software people trust with money and operations data.

Lesson example (start here)

Copy this smaller example first. Once it works, compare it with the real-world code above.

// Capstone service — region revenue + top products
public async Task<AnalyticsSnapshotDto> GetSnapshotAsync(
    AnalyticsFilter filter, CancellationToken ct)
{
    var orders = _context.Orders.AsNoTracking()
        .Where(o => o.OrderDate >= filter.From && o.OrderDate <= filter.To);

    var byRegion = await orders
        .GroupBy(o => o.Region.Name)
        .Select(g => new RegionKpiDto
        {
            Region = g.Key,
            Revenue = g.Sum(o => o.GrandTotal),
            Orders = g.Count()
        })
        .OrderByDescending(x => x.Revenue)
        .Take(10)
        .ToListAsync(ct);

    var topProducts = await _context.OrderItems.AsNoTracking()
        .Where(li => li.Order.OrderDate >= filter.From)
        .GroupBy(li => li.Product.Name)
        .Select(g => new ProductKpiDto { Name = g.Key, Units = g.Sum(x => x.Quantity) })
        .OrderByDescending(x => x.Units)
        .Take(5)
        .ToListAsync(ct);

    return new AnalyticsSnapshotDto { Regions = byRegion, TopProducts = topProducts };
}

Line-by-line walkthrough

How it works (big picture)

• You compose small LINQ pipelines in service methods.
• Controllers stay thin.
• DTOs exit the API boundary.
• Tests use in-memory lists or EF InMemory provider.
• Document one before/after performance fix in README.

Do this on your computer

1. Clone or create the ShopNest.Analytics folder structure.
2. write product search from lesson 91.
3. Add GetSnapshotAsync with GroupBy KPIs.
4. Write two unit tests: search filter and region revenue.
5. Record a 3-minute Loom demo for your portfolio.
6. Read the real-world section and name which part of the app uses this topic.
7. Run the example in a console app or LINQPad and confirm the output.
8. Change one filter or sort in the example and predict the result before you run it.

Experiments — try changing this

• Change a filter value (price, date, name) and run again — see how results change.
• Remove one operator from the chain, run, and read the error or different output.
• Make the Where condition always false — confirm you get zero results.

Remember

Capstone = search + reports + EF Core + tests + README. You have the full LINQ path from lesson 1 to production shape. Ship one demo URL — that beats listing 100 certificates.

Common questions