sql, sqltelemetry: add telemetry counter for external statement hints

Informs: #153633

Release note: None

Author: michae2

pkg/sql/conn_executor_exec.go

@@ -574,6 +574,10 @@ func (ex *connExecutor) execStmtInOpenState(
 		ast = stmt.Statement.AST
 	}
 
+	if len(stmt.Hints) > 0 {
+		telemetry.Inc(sqltelemetry.StatementHintsCounter)
+	}
+
 	// This goroutine is the only one that can modify txnState.mu.priority and
 	// txnState.mu.autoRetryCounter, so we don't need to get a mutex here.
 	ctx = ih.Setup(ctx, ex, p, &stmt, os.ImplicitTxn.Get(),
@@ -1474,6 +1478,10 @@ func (ex *connExecutor) execStmtInOpenStateWithPausablePortal(
 		vars.ast = vars.stmt.Statement.AST
 	}
 
+	if len(vars.stmt.Hints) > 0 {
+		telemetry.Inc(sqltelemetry.StatementHintsCounter)
+	}
+
 	// For pausable portal, the instrumentation helper needs to be set up only
 	// when the portal is executed for the first time.
 	//

pkg/sql/sqltelemetry/planning.go

@@ -234,6 +234,10 @@ var PlanClampedHistogramSelectivityCounter = telemetry.GetCounterOnce("sql.plan.
 // a histogram to a minimum value.
 var PlanClampedInequalitySelectivityCounter = telemetry.GetCounterOnce("sql.plan.clamped-inequality-selectivity")
 
+// StatementHintsCounter is to be incremented whenever external statement hints
+// are used.
+var StatementHintsCounter = telemetry.GetCounterOnce("sql.session.statement-hints")
+
 // We can't parameterize these telemetry counters, so just make a bunch of
 // buckets for setting the join reorder limit since the range of reasonable
 // values for the join reorder limit is quite small.