From 08e907c3db3a073e1b542a4c2161364f013ce0e1 Mon Sep 17 00:00:00 2001
From: t8y2 <1156263951@qq.com>
Date: Thu, 23 Jul 2026 19:03:50 +0800
Subject: [PATCH] fix(oracle): preserve timezone-less datetime values

---
 agents/drivers/oracle-go/main.go      | 12 +++++++++++
 agents/drivers/oracle-go/main_test.go | 30 +++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/agents/drivers/oracle-go/main.go b/agents/drivers/oracle-go/main.go
index c272c584c..7c4eefd61 100644
--- a/agents/drivers/oracle-go/main.go
+++ b/agents/drivers/oracle-go/main.go
@@ -3628,6 +3628,10 @@ func normalizeValue(value any, columnTypeName string) any {
 		}
 		return string(v)
 	case time.Time:
+		// Oracle DATE and plain TIMESTAMP are wall-clock values; adding an offset makes clients shift them.
+		if isOracleTimezoneLessDateTime(columnTypeName) {
+			return v.Format("2006-01-02T15:04:05.999999999")
+		}
 		return v.Format(time.RFC3339Nano)
 	case int64, float64, bool, string:
 		return v
@@ -3638,6 +3642,14 @@ func normalizeValue(value any, columnTypeName string) any {
 	}
 }
 
+func isOracleTimezoneLessDateTime(columnTypeName string) bool {
+	normalized := strings.ToUpper(strings.ReplaceAll(strings.TrimSpace(columnTypeName), " ", ""))
+	if normalized == "DATE" || normalized == "TIMESTAMPDTY" || normalized == "TIMESTAMP" {
+		return true
+	}
+	return strings.HasPrefix(normalized, "TIMESTAMP(") && strings.HasSuffix(normalized, ")")
+}
+
 func isOracleBinaryColumnType(columnTypeName string) bool {
 	normalized := strings.ToUpper(strings.ReplaceAll(strings.TrimSpace(columnTypeName), " ", ""))
 	switch normalized {
diff --git a/agents/drivers/oracle-go/main_test.go b/agents/drivers/oracle-go/main_test.go
index 63e532ff4..057bb0784 100644
--- a/agents/drivers/oracle-go/main_test.go
+++ b/agents/drivers/oracle-go/main_test.go
@@ -242,6 +242,36 @@ func TestNormalizeValueKeepsNonBinaryBytesAsText(t *testing.T) {
 	}
 }
 
+func TestNormalizeValueFormatsOracleTimezoneLessDateTimesAsWallClock(t *testing.T) {
+	value := time.Date(2026, time.July, 23, 13, 42, 13, 123456000, time.FixedZone("CST", 8*60*60))
+	tests := []string{
+		"DATE",
+		"TIMESTAMP",
+		"TIMESTAMP(6)",
+		"TimeStampDTY",
+	}
+
+	for _, columnType := range tests {
+		if got := normalizeValue(value, columnType); got != "2026-07-23T13:42:13.123456" {
+			t.Fatalf("normalizeValue time for %q = %#v, want wall-clock value", columnType, got)
+		}
+	}
+}
+
+func TestNormalizeValueKeepsOracleZonedDateTimeOffsets(t *testing.T) {
+	value := time.Date(2026, time.July, 23, 13, 42, 13, 123456000, time.FixedZone("CST", 8*60*60))
+	tests := []string{
+		"TimeStampTZ_DTY",
+		"TIMESTAMP WITH TIME ZONE",
+	}
+
+	for _, columnType := range tests {
+		if got := normalizeValue(value, columnType); got != "2026-07-23T13:42:13.123456+08:00" {
+			t.Fatalf("normalizeValue time for %q = %#v, want RFC3339 offset", columnType, got)
+		}
+	}
+}
+
 func TestNormalizeDDLObjectType(t *testing.T) {
 	tests := map[string]string{
 		"":                  "",