Project: Sales Pipeline Dashboard

A salesPipelineDashboard component showing each Opportunity stage as a column with its total value and count — Module 7 Lesson 1's "aggregation across many records" signal, now actually built.

public inherited sharing class PipelineSelector {
    public static List<AggregateResult> stageTotals() {
        return [
            SELECT StageName stage, COUNT(Id) opportunityCount, SUM(Amount) totalAmount
            FROM Opportunity
            WHERE IsClosed = false
            WITH SECURITY_ENFORCED
            GROUP BY StageName
        ];
    }
}

public inherited sharing class PipelineService {
    public static List<StageSummary> getStageSummaries() {
        List<StageSummary> summaries = new List<StageSummary>();
        for (AggregateResult ar : PipelineSelector.stageTotals()) {
            summaries.add(new StageSummary(
                (String) ar.get('stage'),
                (Integer) ar.get('opportunityCount'),
                (Decimal) ar.get('totalAmount')
            ));
        }
        return summaries;
    }
}

public with sharing class PipelineController {
    @AuraEnabled(cacheable=true)
    public static List<StageSummary> getStageSummaries() {
        return PipelineService.getStageSummaries();
    }
}

GROUP BY StageName with SUM/COUNT is precisely the aggregation LDS's simple record-read model can't express — the Selector (Module 16) isolates this specific aggregate query construction.

<div class="slds-grid slds-wrap slds-gutters">
    <template for:each={stages} for:item="stage">
        <div key={stage.stageName} class="slds-col slds-size_1-of-1 slds-medium-size_1-of-3">
            <div class="slds-box">
                <h3>{stage.stageName}</h3>
                <p>{stage.formattedTotal} — {stage.opportunityCount} deals</p>
            </div>
        </div>
    </template>
</div>

The responsive grid (Module 9) stacks to one column on mobile and three on desktop; formattedTotal would apply the Intl.NumberFormat currency pattern from Module 11's internationalization lesson.