databendlabs · b41sh · Jan 6, 2026 · Jan 5, 2026 · Jan 6, 2026
diff --git a/Cargo.toml b/Cargo.toml
@@ -35,9 +35,9 @@ nom = "8.0.0"
 num-traits = "0.2.19"
 ordered-float = { version = "5.1.0", default-features = false }
 rand = { version = "0.9.2", features = ["small_rng"] }
-ryu = "1.0"
 serde = "1.0"
 serde_json = { version = "1.0", default-features = false, features = ["std"] }
+zmij = "1.0"
 
 [dev-dependencies]
 goldenfile = "1.8"

diff --git a/src/core/databend/util.rs b/src/core/databend/util.rs
@@ -604,7 +604,7 @@ impl ExtensionValue<'_> {
                 writer.write_all(&[EXTENSION_TIMESTAMP_TZ])?;
                 writer.write_all(&v.value.to_be_bytes())?;
                 writer.write_all(&v.offset.to_be_bytes())?;
-                Ok(10)
+                Ok(13)
             }
             ExtensionValue::Interval(v) => {
                 writer.write_all(&[EXTENSION_INTERVAL])?;
@@ -645,11 +645,16 @@ impl ExtensionValue<'_> {
                 ExtensionValue::Timestamp(Timestamp { value })
             }
             EXTENSION_TIMESTAMP_TZ => {
-                if len != 9 {
+                if len != 9 && len != 12 {
                     return Err(Error::InvalidJsonbNumber);
                 }
                 let value = i64::from_be_bytes(bytes[1..9].try_into().unwrap());
-                let offset = i8::from_be_bytes(bytes[9..10].try_into().unwrap());
+                let offset = if len == 9 {
+                    let hours = i8::from_be_bytes(bytes[9..10].try_into().unwrap());
+                    (hours as i32) * 3_600
+                } else {
+                    i32::from_be_bytes(bytes[9..13].try_into().unwrap())
+                };
 
                 ExtensionValue::TimestampTz(TimestampTz { offset, value })
             }

diff --git a/src/extension.rs b/src/extension.rs
@@ -28,6 +28,7 @@ const MICROS_PER_HOUR: i64 = 60 * MICROS_PER_MINUTE;
 const MONTHS_PER_YEAR: i32 = 12;
 
 const TIMESTAMP_FORMAT: &str = "%Y-%m-%d %H:%M:%S%.6f";
+const TIMESTAMP_TIMEZONE_FORMAT: &str = "%Y-%m-%d %H:%M:%S%.6f %z";
 
 /// Represents extended JSON value types that are not supported in standard JSON.
 ///
@@ -80,8 +81,8 @@ pub struct Timestamp {
 /// Standard JSON has no native timezone-aware timestamp type.
 #[derive(Debug, Clone, PartialEq, Eq, Ord, PartialOrd)]
 pub struct TimestampTz {
-    /// Timezone offset in hours from UTC
-    pub offset: i8,
+    /// Timezone offset in seconds from UTC
+    pub offset: i32,
     /// Microseconds since Unix epoch (January 1, 1970 00:00:00 UTC)
     pub value: i64,
 }
@@ -149,58 +150,49 @@ impl Display for TimestampTz {
             nanos = 0;
         }
         let ts = jiff::Timestamp::new(secs, nanos as i32).unwrap();
-        let tz = Offset::constant(self.offset).to_time_zone();
+        let tz_offset = Offset::from_seconds(self.offset).expect("invalid timezone offset seconds");
+        let tz = tz_offset.to_time_zone();
         let zoned = ts.to_zoned(tz);
 
-        write!(f, "{}", strtime::format(TIMESTAMP_FORMAT, &zoned).unwrap())
+        write!(
+            f,
+            "{}",
+            strtime::format(TIMESTAMP_TIMEZONE_FORMAT, &zoned).unwrap()
+        )
     }
 }
 
 impl Display for Interval {
     fn fmt(&self, f: &mut Formatter) -> std::fmt::Result {
-        let mut date_parts = vec![];
+        let mut wrote_date_part = false;
         let years = self.months / MONTHS_PER_YEAR;
         let months = self.months % MONTHS_PER_YEAR;
-        match years.cmp(&1) {
-            Ordering::Equal => {
-                date_parts.push((years, "year"));
-            }
-            Ordering::Greater => {
-                date_parts.push((years, "years"));
-            }
-            _ => {}
-        }
-        match months.cmp(&1) {
-            Ordering::Equal => {
-                date_parts.push((months, "month"));
-            }
-            Ordering::Greater => {
-                date_parts.push((months, "months"));
-            }
-            _ => {}
-        }
-        match self.days.cmp(&1) {
-            Ordering::Equal => {
-                date_parts.push((self.days, "day"));
-            }
-            Ordering::Greater => {
-                date_parts.push((self.days, "days"));
-            }
-            _ => {}
-        }
-        if !date_parts.is_empty() {
-            for (i, (val, name)) in date_parts.into_iter().enumerate() {
-                if i > 0 {
+
+        let mut write_component = |value: i32, singular: &str, plural: &str| -> std::fmt::Result {
+            if value != 0 {
+                if wrote_date_part {
                     write!(f, " ")?;
                 }
-                write!(f, "{} {}", val, name)?;
-            }
-            if self.micros != 0 {
-                write!(f, " ")?;
+                let abs_val = value.abs();
+                let unit = if abs_val == 1 { singular } else { plural };
+                if value < 0 {
+                    write!(f, "-{} {}", abs_val, unit)?;
+                } else {
+                    write!(f, "{} {}", abs_val, unit)?;
+                }
+                wrote_date_part = true;
             }
-        }
+            Ok(())
+        };
+
+        write_component(years, "year", "years")?;
+        write_component(months, "month", "months")?;
+        write_component(self.days, "day", "days")?;
 
         if self.micros != 0 {
+            if wrote_date_part {
+                write!(f, " ")?;
+            }
             let mut micros = self.micros;
             if micros < 0 {
                 write!(f, "-")?;
@@ -221,7 +213,7 @@ impl Display for Interval {
             if micros != 0 {
                 write!(f, ".{:06}", micros)?;
             }
-        } else if self.months == 0 && self.days == 0 {
+        } else if !wrote_date_part {
             write!(f, "00:00:00")?;
         }
         Ok(())

diff --git a/src/functions/scalar.rs b/src/functions/scalar.rs
@@ -1783,7 +1783,7 @@ impl RawJsonb<'_> {
     /// use jsonb::Value;
     ///
     /// // TimestampTz value
-    /// let timestamp_tz_value = Value::TimestampTz(TimestampTz { offset: 8, value: 1760140800000000 });
+    /// let timestamp_tz_value = Value::TimestampTz(TimestampTz { offset: 8 * 3600, value: 1760140800000000 });
     /// let buf = timestamp_tz_value.to_vec();
     /// let raw_jsonb = RawJsonb::new(&buf);
     /// assert!(raw_jsonb.is_timestamp_tz().unwrap());
@@ -1830,10 +1830,10 @@ impl RawJsonb<'_> {
     /// use jsonb::Value;
     ///
     /// // TimestampTz value
-    /// let timestamp_tz_value = Value::TimestampTz(TimestampTz { offset: 8, value: 1760140800000000 });
+    /// let timestamp_tz_value = Value::TimestampTz(TimestampTz { offset: 8 * 3600, value: 1760140800000000 });
     /// let buf = timestamp_tz_value.to_vec();
     /// let raw_jsonb = RawJsonb::new(&buf);
-    /// assert_eq!(raw_jsonb.as_timestamp_tz().unwrap(), Some(TimestampTz { offset: 8, value: 1760140800000000 }));
+    /// assert_eq!(raw_jsonb.as_timestamp_tz().unwrap(), Some(TimestampTz { offset: 8 * 3600, value: 1760140800000000 }));
     /// ```
     pub fn as_timestamp_tz(&self) -> Result<Option<TimestampTz>> {
         let jsonb_item = JsonbItem::from_raw_jsonb(*self)?;

diff --git a/src/number.rs b/src/number.rs
@@ -1174,7 +1174,7 @@ impl Display for Number {
                 write!(f, "{}", s)
             }
             Number::Float64(v) => {
-                let mut buffer = ryu::Buffer::new();
+                let mut buffer = zmij::Buffer::new();
                 let s = buffer.format(*v);
                 write!(f, "{}", s)
             }

diff --git a/tests/it/decode.rs b/tests/it/decode.rs
@@ -245,10 +245,18 @@ fn test_decode_extension() {
                 value: 1760140800000000,
             }),
         ),
+        // Backward-compatible implementation with offset as int8 hours
         (
             b"\x20\0\0\0\x60\0\0\x0a\x30\0\x06\x40\xd6\xb7\x23\x80\0\x08".to_vec(),
             Value::TimestampTz(TimestampTz {
-                offset: 8,
+                offset: 8 * 3600,
+                value: 1760140800000000,
+            }),
+        ),
+        (
+            b"\x20\0\0\0\x60\0\0\x0d\x30\0\x06\x40\xd6\xb7\x23\x80\0\0\0\x70\x80".to_vec(),
+            Value::TimestampTz(TimestampTz {
+                offset: 8 * 3600,
                 value: 1760140800000000,
             }),
         ),

diff --git a/tests/it/encode.rs b/tests/it/encode.rs
@@ -177,11 +177,11 @@ fn test_encode_array() {
             Value::Binary(&[100, 101, 102, 103]),
             Value::Date(Date {value: 20381 }),
             Value::Timestamp(Timestamp { value: 1540230120000000 }),
-            Value::TimestampTz(TimestampTz { offset: 8, value: 1670389100000000 }),
+            Value::TimestampTz(TimestampTz { offset: 8 * 3600, value: 1670389100000000 }),
             Value::Interval(Interval { months: 2, days: 10, micros: 500000000 }),
             Value::Number(Number::Decimal256(Decimal256 { scale: 2, value: I256::new(1234) })),
         ]).to_vec(),
-        b"\x80\0\0\x07\x30\0\0\0\x60\0\0\x05\x60\0\0\x05\x60\0\0\x09\x60\0\0\x0A\x60\0\0\x11\x20\0\0\x22\0\x64\x65\x66\x67\x10\0\0\x4F\x9D\x20\0\x05\x78\xD4\xC5\x2C\xCA\0\x30\0\x05\xEF\x35\xC4\xF1\x33\0\x08\x40\0\0\0\x02\0\0\0\x0A\0\0\0\0\x1D\xCD\x65\0\x70\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\x04\xD2\x02",
+        b"\x80\0\0\x07\x30\0\0\0\x60\0\0\x05\x60\0\0\x05\x60\0\0\x09\x60\0\0\x0D\x60\0\0\x11\x20\0\0\x22\0\x64\x65\x66\x67\x10\0\0\x4F\x9D\x20\0\x05\x78\xD4\xC5\x2C\xCA\0\x30\0\x05\xEF\x35\xC4\xF1\x33\0\0\0\x70\x80\x40\0\0\0\x02\0\0\0\x0A\0\0\0\0\x1D\xCD\x65\0\x70\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\x04\xD2\x02",
     );
 }
 
@@ -207,7 +207,7 @@ fn test_encode_object() {
     obj2.insert(
         "k5".to_string(),
         Value::TimestampTz(TimestampTz {
-            offset: 8,
+            offset: 8 * 3600,
             value: 1670389100000000,
         }),
     );
@@ -229,7 +229,7 @@ fn test_encode_object() {
 
     assert_eq!(
         &Value::Object(obj2).to_vec(),
-        b"\x40\0\0\x07\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x60\0\0\x05\x60\0\0\x05\x60\0\0\x09\x60\0\0\x0A\x60\0\0\x11\x20\0\0\x22\x6B\x31\x6B\x32\x6B\x33\x6B\x34\x6B\x35\x6B\x36\x6B\x37\x76\x31\0\xC8\xC9\xCA\xCB\x10\0\0\x4F\x9D\x20\0\x05\x78\xD4\xC5\x2C\xCA\0\x30\0\x05\xEF\x35\xC4\xF1\x33\0\x08\x40\0\0\0\x02\0\0\0\x0A\0\0\0\0\x1D\xCD\x65\0\x70\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\x04\xD2\x02"
+        b"\x40\0\0\x07\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x10\0\0\x02\x60\0\0\x05\x60\0\0\x05\x60\0\0\x09\x60\0\0\x0D\x60\0\0\x11\x20\0\0\x22\x6B\x31\x6B\x32\x6B\x33\x6B\x34\x6B\x35\x6B\x36\x6B\x37\x76\x31\0\xC8\xC9\xCA\xCB\x10\0\0\x4F\x9D\x20\0\x05\x78\xD4\xC5\x2C\xCA\0\x30\0\x05\xEF\x35\xC4\xF1\x33\0\0\0\x70\x80\x40\0\0\0\x02\0\0\0\x0A\0\0\0\0\x1D\xCD\x65\0\x70\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\x04\xD2\x02"
     );
 }
 
@@ -252,11 +252,11 @@ fn test_encode_extension() {
     );
     assert_eq!(
         Value::TimestampTz(TimestampTz {
-            offset: 8,
+            offset: 8 * 3600,
             value: 1760140800000000
         })
         .to_vec(),
-        b"\x20\0\0\0\x60\0\0\x0a\x30\0\x06\x40\xd6\xb7\x23\x80\0\x08"
+        b"\x20\0\0\0\x60\0\0\x0d\x30\0\x06\x40\xd6\xb7\x23\x80\0\0\0\x70\x80"
     );
     assert_eq!(
         Value::Interval(Interval {

diff --git a/tests/it/functions.rs b/tests/it/functions.rs
@@ -826,19 +826,32 @@ fn test_to_string() {
 
     let extension_sources = vec![
         (Value::Binary(&[97, 98, 99]), r#""616263""#),
+        (Value::Binary(&[]), r#""""#),
         (Value::Date(Date { value: 90570 }), r#""2217-12-22""#),
+        (Value::Date(Date { value: -1 }), r#""1969-12-31""#),
         (
             Value::Timestamp(Timestamp {
                 value: 190390000000,
             }),
             r#""1970-01-03 04:53:10.000000""#,
         ),
+        (
+            Value::Timestamp(Timestamp { value: 0 }),
+            r#""1970-01-01 00:00:00.000000""#,
+        ),
         (
             Value::TimestampTz(TimestampTz {
-                offset: 8,
+                offset: 8 * 3600,
                 value: 190390000000,
             }),
-            r#""1970-01-03 12:53:10.000000""#,
+            r#""1970-01-03 12:53:10.000000 +0800""#,
+        ),
+        (
+            Value::TimestampTz(TimestampTz {
+                offset: 90 * 60,
+                value: 0,
+            }),
+            r#""1970-01-01 01:30:00.000000 +0130""#,
         ),
         (
             Value::Interval(Interval {
@@ -848,13 +861,52 @@ fn test_to_string() {
             }),
             r#""10 months 20 days 00:05:00""#,
         ),
+        (
+            Value::Interval(Interval {
+                months: -14,
+                days: -3,
+                micros: -90000000,
+            }),
+            r#""-1 year -2 months -3 days -00:01:30""#,
+        ),
+        (
+            Value::Interval(Interval {
+                months: -25,
+                days: -1,
+                micros: 0,
+            }),
+            r#""-2 years -1 month -1 day""#,
+        ),
+        (
+            Value::Interval(Interval {
+                months: 0,
+                days: -2,
+                micros: 5_000_000,
+            }),
+            r#""-2 days 00:00:05""#,
+        ),
+        (
+            Value::Interval(Interval {
+                months: 0,
+                days: 0,
+                micros: 0,
+            }),
+            r#""00:00:00""#,
+        ),
         (
             Value::Number(Number::Decimal128(Decimal128 {
                 scale: 2,
                 value: 1234,
             })),
             r#"12.34"#,
         ),
+        (
+            Value::Number(Number::Decimal64(Decimal64 {
+                scale: 2,
+                value: -765,
+            })),
+            r#"-7.65"#,
+        ),
         (
             Value::Number(Number::Decimal256(Decimal256 {
                 scale: 2,
@@ -870,7 +922,7 @@ fn test_to_string() {
                     value: 190390000000,
                 }),
                 Value::TimestampTz(TimestampTz {
-                    offset: 8,
+                    offset: 8 * 3600,
                     value: 190390000000,
                 }),
                 Value::Interval(Interval {
@@ -887,7 +939,7 @@ fn test_to_string() {
                     value: I256::new(981724),
                 })),
             ]),
-            r#"["616263","2217-12-22","1970-01-03 04:53:10.000000","1970-01-03 12:53:10.000000","10 months 20 days 00:05:00",12.34,9817.24]"#,
+            r#"["616263","2217-12-22","1970-01-03 04:53:10.000000","1970-01-03 12:53:10.000000 +0800","10 months 20 days 00:05:00",12.34,9817.24]"#,
         ),
         (
             Value::Object(BTreeMap::from([
@@ -902,7 +954,7 @@ fn test_to_string() {
                 (
                     "k4".to_string(),
                     Value::TimestampTz(TimestampTz {
-                        offset: 8,
+                        offset: 8 * 3600,
                         value: 190390000000,
                     }),
                 ),
@@ -929,7 +981,7 @@ fn test_to_string() {
                     })),
                 ),
             ])),
-            r#"{"k1":"616263","k2":"2217-12-22","k3":"1970-01-03 04:53:10.000000","k4":"1970-01-03 12:53:10.000000","k5":"10 months 20 days 00:05:00","k6":12.34,"k7":9817.24}"#,
+            r#"{"k1":"616263","k2":"2217-12-22","k3":"1970-01-03 04:53:10.000000","k4":"1970-01-03 12:53:10.000000 +0800","k5":"10 months 20 days 00:05:00","k6":12.34,"k7":9817.24}"#,
         ),
     ];
 
@@ -1117,7 +1169,7 @@ fn test_type_of() {
         ),
         (
             Value::TimestampTz(TimestampTz {
-                offset: 8,
+                offset: 8 * 3600,
                 value: 190390000000,
             }),
             "TIMESTAMP_TZ",