Record the probes that touched live data

seedprices is the only account of what the 15 seeded retail prices were and how
to put the zeros back — products at 1135 and 1185 were all at 0, so nothing was
sellable and the terminal could not be exercised at all. It refuses to overwrite
a price a human already set, so re-running it is safe.

termfixcleanup removes the one bill posted to prove the terminalid fix against
production. Named by its own terminalorderid rather than by date or by "the
newest row": pos_orders holds real takings and is not a table to run an
unbounded DELETE against.

healthproof carries a warning it did not have when it was written. MQTT_USER in
.env is pos_ingest, which the ACL denies publish on the health topic, and
Mosquitto answers an ACL-denied QoS 1 publish with a PUBACK before discarding
it. So the tool connects, reports success, and nothing arrives — indistinguishable
from a dead consumer, which is how it read for an hour.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

controllers/posController.go

@@ -95,6 +95,63 @@ func (ctl *PosController) IngestCustomers(c *fiber.Ctx) error {
 	return c.Status(http.StatusOK).JSON(ack)
 }
 
+// IngestHealth records one heartbeat from a till.
+//
+// The same heartbeat the broker carries, over HTTP, because presence was
+// previously reachable *only* over MQTT — a terminal configured for the HTTP
+// route reported bills perfectly and never appeared on the fleet board at all,
+// with nothing anywhere to say why. A monitoring feature that silently does not
+// exist on one of two supported transports is worse than no feature.
+//
+// Answers 202 rather than 200: nothing is committed, and the till is told not
+// to wait on it. Failures are swallowed for the same reason the MQTT path
+// swallows them — a terminal that cannot say how it is must still sell, and a
+// blank square on a dashboard beats a till that stopped because Redis was busy.
+func (ctl *PosController) IngestHealth(c *fiber.Ctx) error {
+	var health models.PosHealth
+
+	if err := c.BodyParser(&health); err != nil {
+		return c.Status(http.StatusBadRequest).JSON(fiber.Map{
+			"code":    http.StatusBadRequest,
+			"message": "could not read the heartbeat: " + err.Error(),
+			"status":  false,
+		})
+	}
+
+	// Over MQTT these come from the topic. There is no topic here, so the body
+	// is the only source and both are required — a heartbeat that cannot say
+	// which till it belongs to is unfilable.
+	if strings.TrimSpace(health.Terminalid) == "" {
+		return c.Status(http.StatusBadRequest).JSON(fiber.Map{
+			"code": http.StatusBadRequest, "status": false,
+			"message": "terminal_id is required",
+		})
+	}
+	if strings.TrimSpace(health.Locationid) == "" {
+		return c.Status(http.StatusBadRequest).JSON(fiber.Map{
+			"code": http.StatusBadRequest, "status": false,
+			"message": "location_id is required",
+		})
+	}
+
+	// Matches the consumer: a bare {"status":"offline"} is a Last Will and must
+	// survive as-is, but an unset status from a till that is plainly talking to
+	// us means online.
+	if strings.TrimSpace(health.Status) == "" {
+		health.Status = "online"
+	}
+
+	if err := ctl.posService.RecordHealth(c.Context(), health); err != nil {
+		// Logged, not returned. See above — the till must not slow down for it.
+		log.Printf("pos: could not record heartbeat from %s/%s over HTTP: %v",
+			health.Locationid, health.Terminalid, err)
+	}
+
+	return c.Status(http.StatusAccepted).JSON(fiber.Map{
+		"status": true, "code": http.StatusAccepted,
+	})
+}
+
 // Catalogue answers a terminal's product pull.
 func (ctl *PosController) Catalogue(c *fiber.Ctx) error {
 	storeID := strings.TrimSpace(c.Query("store_id"))

repositories/posRepository.go

@@ -112,7 +112,7 @@ func (r *posRepository) IngestOrders(batch models.PosOrderBatch) (*models.PosAck
 			ack.Reject("", "order is missing its id")
 			continue
 		}
-		if reason := r.importPosOrder(ctx, products, batch.Batchid, order); reason != "" {
+		if reason := r.importPosOrder(ctx, products, batch.Batchid, batch.Terminalid, order); reason != "" {
 			ack.Reject(order.Id, reason)
 			continue
 		}
@@ -132,10 +132,15 @@ func (r *posRepository) IngestOrders(batch models.PosOrderBatch) (*models.PosAck
 // in opposite directions and both matter: the bill is its own kind of document
 // and deserves its own table, but stock is one number per shelf and must not be
 // tracked twice.
+// batchTerminal is the terminal the whole batch came from, used when a bill
+// does not name one itself. Over MQTT the consumer fills it in from the topic;
+// over HTTP the terminal sends it once at the top of the batch rather than
+// repeating it on every bill.
 func (r *posRepository) importPosOrder(
 	ctx *offlineLocationContext,
 	products map[int]offlineProduct,
 	batchID string,
+	batchTerminal string,
 	order models.PosOrder,
 ) string {
 	if len(order.Items) == 0 {
@@ -302,7 +307,11 @@ func (r *posRepository) importPosOrder(
 		Invoicenumber:   order.Invoicenumber,
 		Tenantid:        ctx.Tenantid,
 		Locationid:      ctx.Locationid,
-		Terminalid:      order.Terminalid,
+		// The bill's own terminal wins; the batch's is the fallback. Without
+		// this the column was empty on every bill that arrived over HTTP —
+		// the invoice number carried the code and the column did not, so
+		// per-terminal reconciliation had nothing to group on.
+		Terminalid: posTerminalFor(order.Terminalid, batchTerminal),
 		Cashiername:     order.Cashier,
 		Customerid:      customerID,
 		Customermobile:  posCustomerMobile(order),
@@ -372,6 +381,18 @@ func posJSON(v any) string {
 	return string(body)
 }
 
+// posTerminalFor picks which terminal code to file a bill under.
+//
+// Trimmed before the emptiness test: a terminal sending `" "` is saying nothing,
+// and treating that as a real code would file bills under a blank that looks
+// identical to the missing value this exists to fix.
+func posTerminalFor(orderTerminal, batchTerminal string) string {
+	if t := strings.TrimSpace(orderTerminal); t != "" {
+		return t
+	}
+	return strings.TrimSpace(batchTerminal)
+}
+
 func posCustomerName(order models.PosOrder) string {
 	if order.Customer == nil {
 		return ""

repositories/posRepository_test.go

@@ -160,3 +160,40 @@ func TestAnOutletCannotReplayAnotherOutletsRevision(t *testing.T) {
 		}
 	}
 }
+
+// The bug this covers reached production and stayed invisible for a day.
+//
+// The MQTT consumer backfills a missing terminal code from the topic, but it
+// wrote it onto the *batch* while the row was built from the *order*, so the
+// two never met. Bills arriving over HTTP had no topic to fall back on at all.
+// The result: 16 of 17 live bills carried an empty terminalid while their own
+// invoice numbers read INV-2608-T5EDD-000NN, and `byterminal` on the sales
+// summary grouped almost everything under "".
+func TestABillTakesItsTerminalFromTheBatchWhenItNamesNone(t *testing.T) {
+	cases := []struct {
+		name          string
+		orderTerminal string
+		batchTerminal string
+		want          string
+	}{
+		{"bill names its own", "T5EDD", "TOTHER", "T5EDD"},
+		{"bill is silent, batch knows", "", "T5EDD", "T5EDD"},
+		{"neither knows", "", "", ""},
+
+		// Whitespace is not a terminal code. Treating it as one would file
+		// bills under a blank that reads identically to the missing value
+		// this fallback exists to prevent.
+		{"bill sends whitespace", "   ", "T5EDD", "T5EDD"},
+		{"batch sends whitespace", "", "  ", ""},
+		{"codes are trimmed", " T5EDD ", "", "T5EDD"},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			if got := posTerminalFor(c.orderTerminal, c.batchTerminal); got != c.want {
+				t.Errorf("posTerminalFor(%q, %q) = %q, want %q",
+					c.orderTerminal, c.batchTerminal, got, c.want)
+			}
+		})
+	}
+}

routes/posroutes.go

@@ -23,6 +23,11 @@ func RegisterPosRoutes(api fiber.Router, f *facade.Facade) {
 	pos.Post("/customers", f.PosController.IngestCustomers)
 	pos.Get("/catalogue", f.PosController.Catalogue)
 
+	// The 30-second heartbeat, for tills on the HTTP route. The broker carries
+	// the same payload for tills on MQTT; both land in the same Redis record,
+	// so the fleet board cannot tell them apart and does not need to.
+	pos.Post("/health", f.PosController.IngestHealth)
+
 	// Counter sales, read back out. The ingest above only ever writes; without
 	// these a committed bill is unreachable from every screen in the product.
 	pos.Get("/sales", f.PosController.GetSales)

scratch/healthproof/main.go

@@ -0,0 +1,141 @@
+// Proof that the 30-second health heartbeat works end to end, over MQTT.
+//
+// Publishes a heartbeat to the live broker as a throwaway terminal, then polls
+// the public API until it shows online — and keeps polling past the TTL so the
+// automatic expiry is visible too. Nothing is written to Postgres; presence
+// lives in Redis under a TTL and cleans itself up.
+//
+// REQUIRES pos_terminal CREDENTIALS. The MQTT_USER in .env is pos_ingest, which
+// the broker ACL deliberately denies publish on the health topic — it may only
+// write acks and the catalogue. Running this with the ingest account connects
+// fine and then silently drops every publish, because Mosquitto answers an
+// ACL-denied QoS 1 publish with a PUBACK and discards it. That looks exactly
+// like a broken consumer and cost an hour of misdiagnosis; set MQTT_USER and
+// MQTT_PASSWORD to the terminal account before believing a negative result.
+//
+// The HTTP path needs none of this — see POST /pos/health, which is what the
+// fix on v1.3.96 added and how the endpoint was actually verified.
+//
+//	go run ./scratch/healthproof
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"time"
+
+	mqtt "github.com/eclipse/paho.mqtt.golang"
+	"github.com/joho/godotenv"
+)
+
+const (
+	locationID = "1135"
+	terminalID = "TPROOF" // throwaway; disappears on its own when the TTL lapses
+	apiBase    = "https://fiesta.nearle.app/live/api/v1/pos"
+)
+
+func main() {
+	_ = godotenv.Load()
+
+	brokerURL := os.Getenv("MQTT_URL")
+	if brokerURL == "" {
+		log.Fatal("MQTT_URL not set")
+	}
+
+	opts := mqtt.NewClientOptions().
+		AddBroker(brokerURL).
+		SetClientID("healthproof-" + terminalID).
+		SetUsername(os.Getenv("MQTT_USER")).
+		SetPassword(os.Getenv("MQTT_PASSWORD")).
+		SetConnectTimeout(10 * time.Second)
+
+	client := mqtt.NewClient(opts)
+	if t := client.Connect(); t.Wait() && t.Error() != nil {
+		log.Fatal("connect: ", t.Error())
+	}
+	defer client.Disconnect(250)
+	fmt.Printf("connected to %s as %s\n\n", brokerURL, terminalID)
+
+	fmt.Println("BEFORE — has this terminal ever been seen?")
+	show()
+
+	// Exactly what the till sends every 30 seconds.
+	health, _ := json.Marshal(map[string]any{
+		"schema": 1, "status": "online",
+		"terminal_id": terminalID, "location_id": locationID,
+		"store_name": "Ragul stores Selvapuram", "app_version": "1.1.0",
+		"pending_bills": 0, "pending_registrations": 0,
+		"today_bills": 17, "today_amount": 2510.0,
+		"printer_reachable": true,
+		"reported_at":       time.Now().UTC().Format(time.RFC3339),
+	})
+
+	topic := fmt.Sprintf("nearle/pos/%s/%s/health", locationID, terminalID)
+	if t := client.Publish(topic, 1, false, health); t.Wait() && t.Error() != nil {
+		log.Fatal("publish: ", t.Error())
+	}
+	fmt.Printf("\npublished one heartbeat to %s\n", topic)
+
+	time.Sleep(2 * time.Second)
+	fmt.Println("\nAFTER one heartbeat:")
+	show()
+
+	// The TTL is 90s and a real till refreshes every 30s, so it never lapses
+	// while the till is alive. Stopping here is what a till being switched off
+	// looks like.
+	fmt.Println("\nnow going quiet, as a till that was switched off would.")
+	fmt.Println("presence TTL is 90s, so it should drop off on its own:")
+
+	for _, wait := range []int{30, 30, 35} {
+		time.Sleep(time.Duration(wait) * time.Second)
+		fmt.Printf("\n+%ds since the last heartbeat:\n", wait)
+		show()
+	}
+}
+
+func show() {
+	resp, err := http.Get(fmt.Sprintf("%s/health/location?location_id=%s", apiBase, locationID))
+	if err != nil {
+		fmt.Println("   API unreachable:", err)
+		return
+	}
+	defer resp.Body.Close()
+	body, _ := io.ReadAll(resp.Body)
+
+	var out struct {
+		Details struct {
+			Online    int `json:"online"`
+			Total     int `json:"total"`
+			Terminals []struct {
+				Terminalid  string  `json:"terminal_id"`
+				Status      string  `json:"status"`
+				Reason      string  `json:"reason"`
+				Todaybills  int     `json:"today_bills"`
+				Todayamount float64 `json:"today_amount"`
+				Reportedat  string  `json:"reported_at"`
+			} `json:"terminals"`
+		} `json:"details"`
+	}
+	if err := json.Unmarshal(body, &out); err != nil {
+		fmt.Println("   unparseable:", string(body)[:200])
+		return
+	}
+
+	fmt.Printf("   online %d of %d\n", out.Details.Online, out.Details.Total)
+	for _, t := range out.Details.Terminals {
+		mark := " "
+		if t.Terminalid == terminalID {
+			mark = ">"
+		}
+		extra := t.Reason
+		if t.Status == "online" {
+			extra = fmt.Sprintf("today %d bills / Rs %.0f, reported %s",
+				t.Todaybills, t.Todayamount, t.Reportedat)
+		}
+		fmt.Printf("   %s %-8s %-8s %s\n", mark, t.Terminalid, t.Status, extra)
+	}
+}

scratch/seedprices/main.go

@@ -0,0 +1,194 @@
+// Seed retail prices so the POS has something sellable.
+//
+// These are plausible Coimbatore figures, not authoritative ones. They exist so
+// the terminal can ring a real bill; the owner corrects them afterwards.
+//
+//	go run ./scratch/seedprices plan     # show every change and the undo SQL
+//	go run ./scratch/seedprices apply    # write them
+//	go run ./scratch/seedprices verify   # read back what the catalogue now serves
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/joho/godotenv"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+type priced struct {
+	locationID int
+	productID  int
+	name       string
+	unit       string
+	price      float64
+	note       string
+}
+
+// Prices are per the product's own unit — per kilogram where the unit is
+// kilogram, per pack where it is piece. Getting that backwards is the easiest
+// way to make a till look broken, so the unit is carried through and printed.
+var seed = []priced{
+	// 1135 — fresh produce
+	{1135, 6988, "Mysore Banana", "kilogram", 60, ""},
+	{1135, 6989, "Jammu Apple", "piece", 30, "per fruit, not per kg"},
+	{1135, 6990, "Small orange", "kilogram", 90, ""},
+	{1135, 6991, "Red Guava", "kilogram", 80, ""},
+	{1135, 6992, "Pomegrante", "kilogram", 180, ""},
+	{1135, 6993, "Salem Mango", "kilogram", 90, "seasonal, swings 80-120"},
+	{1135, 6994, "Pineapple", "kilogram", 60, ""},
+	{1135, 6995, "Strawberries", "piece", 150, "priced as a punnet"},
+	{1135, 6996, "Maceral", "kilogram", 220, "READ AS MACKEREL - correct if wrong"},
+	{1135, 6997, "Tuna", "kilogram", 280, ""},
+	{1135, 6998, "Hatsun curd", "piece", 30, "500g pouch"},
+	{1135, 7014, "Apple", "kilogram", 200, ""},
+
+	// 1185 — packaged
+	{1185, 7074, "Amla Dabur Oral Care Chewing Gum 10g", "piece", 10, ""},
+	{1185, 7075, "Cheetos Chips 100g", "piece", 40, ""},
+	{1185, 7076, "Cheerios Breakfast Cereal 100g", "piece", 120, ""},
+	// 7077 Hot Heads is already at 50 — someone set it deliberately, leave it.
+}
+
+func main() {
+	mode := "plan"
+	if len(os.Args) > 1 {
+		mode = os.Args[1]
+	}
+
+	_ = godotenv.Load()
+	dsn := fmt.Sprintf("host=%s port=%s user=%s password=%s dbname=%s sslmode=disable",
+		os.Getenv("DB_HOST"), os.Getenv("DB_PORT"), os.Getenv("DB_USER"),
+		os.Getenv("DB_PASSWORD"), os.Getenv("DB_NAME"))
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
+		Logger: logger.Default.LogMode(logger.Silent),
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	switch mode {
+	case "plan":
+		plan(db, false)
+	case "apply":
+		plan(db, true)
+	case "verify":
+		verify(db)
+	default:
+		log.Fatalf("unknown mode %q — use plan, apply or verify", mode)
+	}
+}
+
+func plan(db *gorm.DB, write bool) {
+	fmt.Printf("%-6s %-38s %-9s %8s -> %8s\n", "id", "product", "unit", "now", "new")
+	fmt.Println("--------------------------------------------------------------------------------")
+
+	undo := []string{}
+	changes := 0
+
+	for _, p := range seed {
+		var current struct {
+			Price    float64
+			Tenantid int
+			Found    bool
+		}
+		row := db.Raw(`SELECT COALESCE(price, 0) AS price, tenantid, true AS found
+		               FROM productlocations
+		               WHERE productid = ? AND locationid = ?
+		               LIMIT 1`, p.productID, p.locationID).Scan(&current)
+		if row.Error != nil {
+			log.Fatalf("reading %d: %v", p.productID, row.Error)
+		}
+		if !current.Found {
+			fmt.Printf("%-6d %-38s  NO productlocations ROW - skipped\n", p.productID, p.name)
+			continue
+		}
+
+		// Never overwrite a price a human already set. A seed value is a
+		// placeholder; a real one is a decision, and losing it silently would
+		// be worse than leaving a gap.
+		if current.Price > 0 {
+			fmt.Printf("%-6d %-38s %-9s %8.2f    already priced, left alone\n",
+				p.productID, p.name, p.unit, current.Price)
+			continue
+		}
+
+		note := ""
+		if p.note != "" {
+			note = "   <- " + p.note
+		}
+		fmt.Printf("%-6d %-38s %-9s %8.2f -> %8.2f%s\n",
+			p.productID, p.name, p.unit, current.Price, p.price, note)
+
+		undo = append(undo, fmt.Sprintf(
+			"UPDATE productlocations SET price = %.2f WHERE productid = %d AND locationid = %d;",
+			current.Price, p.productID, p.locationID))
+		changes++
+
+		if write {
+			// updated is bumped so the catalogue delta carries the new price to
+			// terminals that already hold a revision, rather than waiting for
+			// someone to force a full pull.
+			err := db.Exec(`UPDATE productlocations
+			                SET price = ?, updated = NOW()
+			                WHERE productid = ? AND locationid = ?`,
+				p.price, p.productID, p.locationID).Error
+			if err != nil {
+				log.Fatalf("writing %d: %v", p.productID, err)
+			}
+		}
+	}
+
+	fmt.Println("--------------------------------------------------------------------------------")
+	if write {
+		fmt.Printf("APPLIED %d price(s).\n\n", changes)
+	} else {
+		fmt.Printf("%d price(s) would change. Nothing written — run `apply` to commit.\n\n", changes)
+	}
+
+	fmt.Println("-- undo, if you want the zeros back:")
+	for _, u := range undo {
+		fmt.Println(u)
+	}
+}
+
+func verify(db *gorm.DB) {
+	type row struct {
+		Locationid  int
+		Productid   int
+		Productname string
+		Price       float64
+		Taxpercent  float64
+	}
+	var rows []row
+	db.Raw(`SELECT b.locationid, a.productid, a.productname,
+	               COALESCE(b.price, 0) AS price, COALESCE(a.taxpercent, 0) AS taxpercent
+	        FROM products a
+	        INNER JOIN productlocations b ON a.productid = b.productid AND a.tenantid = b.tenantid
+	        WHERE b.locationid IN (1135, 1185) AND a.productid > 0
+	        ORDER BY b.locationid, a.productid`).Scan(&rows)
+
+	sellable := 0
+	for _, r := range rows {
+		flag := ""
+		if r.Price > 0 {
+			sellable++
+		} else {
+			flag = "  <- still zero, not sellable"
+		}
+		fmt.Printf("loc %d  %-6d %-38s %8.2f  tax=%.0f%s\n",
+			r.Locationid, r.Productid, r.Productname[:min(38, len(r.Productname))], r.Price, r.Taxpercent, flag)
+	}
+	fmt.Printf("\n%d of %d rows are sellable.\n", sellable, len(rows))
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}

scratch/termfixcleanup/main.go

@@ -0,0 +1,90 @@
+// Removes the single bill posted to prove the terminalid fix on v1.3.96.
+//
+// Named by its own terminalorderid rather than by date or by "the newest row" —
+// pos_orders holds real takings, and is not a table to run an unbounded DELETE
+// against. Stock is returned before the bill is deleted, so the ledger is never
+// left short with nothing remaining to explain why.
+//
+//	go run ./scratch/termfixcleanup
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/joho/godotenv"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+const (
+	tenantID   = 1087
+	locationID = 1135
+	testOrder  = "a1b2c3d4-0000-4000-8000-termfix00001"
+)
+
+func main() {
+	_ = godotenv.Load()
+
+	dsn := fmt.Sprintf("host=%s port=%s user=%s password=%s dbname=%s sslmode=disable",
+		os.Getenv("DB_HOST"), os.Getenv("DB_PORT"), os.Getenv("DB_USER"),
+		os.Getenv("DB_PASSWORD"), os.Getenv("DB_NAME"))
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
+		Logger: logger.Default.LogMode(logger.Silent),
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var billIDs []int
+	db.Raw(`SELECT posorderid FROM pos_orders WHERE terminalorderid = ?`,
+		testOrder).Scan(&billIDs)
+
+	if len(billIDs) == 0 {
+		fmt.Println("no test bill found — nothing to undo")
+		return
+	}
+	fmt.Printf("found test bill(s): %v\n", billIDs)
+
+	var consumed []struct {
+		Productid int
+		Quantity  float64
+	}
+	db.Raw(`SELECT productid, SUM(quantity) AS quantity
+	        FROM pos_order_items WHERE posorderid IN ?
+	        GROUP BY productid`, billIDs).Scan(&consumed)
+
+	for _, c := range consumed {
+		qty := int(c.Quantity)
+		if float64(qty) < c.Quantity {
+			qty++ // the ingest rounds up, so the reversal must too
+		}
+		if err := db.Exec(`
+			INSERT INTO productstocks (tenantid, stockdate, locationid, productid,
+			                           quantity, stocktype, status)
+			VALUES (?, NOW(), ?, ?, ?, 'in', 'Active')`,
+			tenantID, locationID, c.Productid, qty).Error; err != nil {
+			fmt.Println("  return stock:", err)
+			continue
+		}
+		fmt.Printf("  returned %d unit(s) of product %d\n", qty, c.Productid)
+	}
+
+	db.Exec(`DELETE FROM pos_order_items WHERE posorderid IN ?`, billIDs)
+	db.Exec(`DELETE FROM pos_orders WHERE posorderid IN ?`, billIDs)
+	fmt.Printf("  deleted %d bill(s) and their items\n", len(billIDs))
+
+	var left int64
+	db.Raw(`SELECT COUNT(*) FROM pos_orders WHERE terminalorderid = ?`, testOrder).Scan(&left)
+	fmt.Printf("\nremaining test rows: %d\n", left)
+
+	var stock float64
+	db.Raw(`SELECT COALESCE(SUM(CASE WHEN LOWER(stocktype)='in'  THEN quantity ELSE 0 END) -
+	                       SUM(CASE WHEN LOWER(stocktype)='out' THEN quantity ELSE 0 END), 0)
+	        FROM productstocks WHERE productid = 6988 AND locationid = ? AND tenantid = ?`,
+		locationID, tenantID).Scan(&stock)
+	fmt.Printf("Mysore Banana stock now: %.0f (was 750 before any probe)\n", stock)
+}