From 4db7f0aa8e5d33a196a9c2361338a690ffedc90d Mon Sep 17 00:00:00 2001
From: hi-rustin <rustin.liu@gmail.com>
Date: Wed, 17 Jul 2024 16:47:44 +0800
Subject: [PATCH] fix

---
 pkg/statistics/handle/storage/json.go | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/pkg/statistics/handle/storage/json.go b/pkg/statistics/handle/storage/json.go
index 701a2ed0383c0..88529945bde14 100644
--- a/pkg/statistics/handle/storage/json.go
+++ b/pkg/statistics/handle/storage/json.go
@@ -143,25 +143,26 @@ func GenJSONTableFromStats(
 	}
 	jsonTbl.ExtStats = dumpJSONExtendedStats(tbl.ExtendedStats)
 	if colStatsUsage != nil {
-		jsonColStatsUsage := make([]*util.JSONPredicateColumn, 0)
+		// nilIfNil checks if the provided *time.Time is nil and returns a nil or its string representation accordingly.
+		nilIfNil := func(t *types.Time) *string {
+			if t == nil {
+				return nil
+			}
+			s := t.String()
+			return &s
+		}
+		jsonColStatsUsage := make([]*util.JSONPredicateColumn, 0, len(colStatsUsage))
 		for id, usage := range colStatsUsage {
 			jsonCol := &util.JSONPredicateColumn{
-				ID: id.ID,
-			}
-			if usage.LastUsedAt != nil {
-				// UTC
-				s := usage.LastUsedAt.String()
-				jsonCol.LastUsedAt = &s
-			}
-			if usage.LastAnalyzedAt != nil {
-				// UTC
-				s := usage.LastAnalyzedAt.String()
-				jsonCol.LastAnalyzedAt = &s
+				ID:             id.ID,
+				LastUsedAt:     nilIfNil(usage.LastUsedAt),
+				LastAnalyzedAt: nilIfNil(usage.LastAnalyzedAt),
 			}
 			jsonColStatsUsage = append(jsonColStatsUsage, jsonCol)
 		}
 		jsonTbl.PredicateColumns = jsonColStatsUsage
 	}
+
 	return jsonTbl, nil
 }