fix(config): tolerate a NULL error when scanning purchase executions

internal/config/store_postgres.go

@@ -2103,6 +2103,9 @@ func scanExecutionRows(rows pgx.Rows) ([]PurchaseExecution, error) {
 		// approval_token_hash is NULL on rows migration 000100 found with no
 		// raw token (every canceled row among them).
 		var approvalTokenHash sql.NullString
+		// error is nullable (migration 000001); one NULL row must not fail the
+		// whole list scan (issue #1465). exec.Error stays "" for those.
+		var errText sql.NullString
 
 		err := rows.Scan(
 			&planID,
@@ -2116,7 +2119,7 @@ func scanExecutionRows(rows pgx.Rows) ([]PurchaseExecution, error) {
 			&exec.TotalUpfrontCost,
 			&exec.EstimatedSavings,
 			&completedAt,
-			&exec.Error,
+			&errText,
 			&expiresAt,
 			&exec.CloudAccountID,
 			&exec.Source,
@@ -2146,6 +2149,7 @@ func scanExecutionRows(rows pgx.Rows) ([]PurchaseExecution, error) {
 			exec.IdempotencyKey = idempotencyKey.String
 		}
 		exec.ApprovalToken = approvalTokenHash.String
+		exec.Error = errText.String
 
 		// Unmarshal recommendations
 		if err := json.Unmarshal(recommendationsJSON, &exec.Recommendations); err != nil {

internal/config/store_postgres_execution_null_error_integration_test.go

@@ -0,0 +1,71 @@
+//go:build integration
+// +build integration
+
+package config
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestIntegration_ExecutionReaders_NullErrorColumn is the issue #1465
+// regression. purchase_executions.error is nullable, and one row with a NULL
+// there used to fail the scan for the whole result set, hiding every
+// actionable execution from the history page and approval queue.
+func TestIntegration_ExecutionReaders_NullErrorColumn(t *testing.T) {
+	ctx := context.Background()
+	store := setupRampStepStore(ctx, t)
+
+	base := time.Now().Add(-time.Hour)
+	saveClean := func(offset int, status string) string {
+		exec := &PurchaseExecution{
+			ExecutionID:    uuid.New().String(),
+			IdempotencyKey: uuid.New().String(),
+			Status:         status,
+			ScheduledDate:  base.Add(time.Duration(offset) * time.Minute),
+		}
+		require.NoError(t, store.SavePurchaseExecution(ctx, exec))
+		return exec.ExecutionID
+	}
+	other := saveClean(1, "pending")
+	nullErr := saveClean(2, "pending")
+	last := saveClean(3, "notified")
+	_, err := store.db.Exec(ctx, `UPDATE purchase_executions SET error = NULL WHERE execution_id = $1`, nullErr)
+	require.NoError(t, err)
+
+	wantIDs := []string{last, nullErr, other}
+	assertAll := func(t *testing.T, got []PurchaseExecution) {
+		t.Helper()
+		ids := make([]string, len(got))
+		for i := range got {
+			ids[i] = got[i].ExecutionID
+			assert.Empty(t, got[i].Error, "NULL error scans as empty string")
+		}
+		assert.Equal(t, wantIDs, ids)
+	}
+
+	statuses := []string{"pending", "notified"}
+	byStatuses, err := store.GetExecutionsByStatuses(ctx, statuses, 100)
+	require.NoError(t, err)
+	assertAll(t, byStatuses)
+
+	page, err := store.ListHistoryExecutionsPage(ctx, HistoryExecutionsPageQuery{Statuses: statuses, Limit: 100})
+	require.NoError(t, err)
+	assertAll(t, page)
+
+	pending, err := store.GetPendingExecutions(ctx)
+	require.NoError(t, err)
+	require.Len(t, pending, 3)
+	for i := range pending {
+		assert.Empty(t, pending[i].Error)
+	}
+
+	single, err := store.GetExecutionByID(ctx, nullErr)
+	require.NoError(t, err)
+	assert.Empty(t, single.Error)
+}