feat: impl Vector, DataType traits for decimal128

Cargo.toml

@@ -134,6 +134,7 @@ common-base = { path = "src/common/base" }
 common-catalog = { path = "src/common/catalog" }
 common-config = { path = "src/common/config" }
 common-datasource = { path = "src/common/datasource" }
+common-decimal = { path = "src/common/decimal" }
 common-error = { path = "src/common/error" }
 common-function = { path = "src/common/function" }
 common-greptimedb-telemetry = { path = "src/common/greptimedb-telemetry" }

src/api/src/helper.rs

@@ -158,7 +158,8 @@ impl TryFrom<ConcreteDataType> for ColumnDataTypeWrapper {
             },
             ConcreteDataType::Null(_)
             | ConcreteDataType::List(_)
-            | ConcreteDataType::Dictionary(_) => {
+            | ConcreteDataType::Dictionary(_)
+            | ConcreteDataType::Decimal128(_) => {
                 return error::IntoColumnDataTypeSnafu { from: datatype }.fail()
             }
         });
@@ -341,7 +342,7 @@ pub fn push_vals(column: &mut Column, origin_count: usize, vector: VectorRef) {
             TimeUnit::Microsecond => values.duration_microsecond_values.push(val.value()),
             TimeUnit::Nanosecond => values.duration_nanosecond_values.push(val.value()),
         },
-        Value::List(_) => unreachable!(),
+        Value::List(_) | Value::Decimal128(_) => unreachable!(),
     });
     column.null_mask = null_mask.into_vec();
 }
@@ -522,7 +523,10 @@ pub fn pb_values_to_vector_ref(data_type: &ConcreteDataType, values: Values) ->
                 values.duration_nanosecond_values,
             )),
         },
-        ConcreteDataType::Null(_) | ConcreteDataType::List(_) | ConcreteDataType::Dictionary(_) => {
+        ConcreteDataType::Null(_)
+        | ConcreteDataType::List(_)
+        | ConcreteDataType::Dictionary(_)
+        | ConcreteDataType::Decimal128(_) => {
             unreachable!()
         }
     }
@@ -692,7 +696,10 @@ pub fn pb_values_to_values(data_type: &ConcreteDataType, values: Values) -> Vec<
             .into_iter()
             .map(|v| Value::Duration(Duration::new_nanosecond(v)))
             .collect(),
-        ConcreteDataType::Null(_) | ConcreteDataType::List(_) | ConcreteDataType::Dictionary(_) => {
+        ConcreteDataType::Null(_)
+        | ConcreteDataType::List(_)
+        | ConcreteDataType::Dictionary(_)
+        | ConcreteDataType::Decimal128(_) => {
             unreachable!()
         }
     }
@@ -816,7 +823,7 @@ pub fn to_proto_value(value: Value) -> Option<v1::Value> {
                 value_data: Some(ValueData::DurationNanosecondValue(v.value())),
             },
         },
-        Value::List(_) => return None,
+        Value::List(_) | Value::Decimal128(_) => return None,
     };
 
     Some(proto_value)
@@ -908,9 +915,10 @@ pub fn to_column_data_type(data_type: &ConcreteDataType) -> Option<ColumnDataTyp
             ColumnDataType::IntervalMonthDayNano
         }
         ConcreteDataType::Interval(IntervalType::DayTime(_)) => ColumnDataType::IntervalDayTime,
-        ConcreteDataType::Null(_) | ConcreteDataType::List(_) | ConcreteDataType::Dictionary(_) => {
-            return None
-        }
+        ConcreteDataType::Null(_)
+        | ConcreteDataType::List(_)
+        | ConcreteDataType::Dictionary(_)
+        | ConcreteDataType::Decimal128(_) => return None,
     };
 
     Some(column_data_type)
@@ -974,7 +982,7 @@ pub fn value_to_grpc_value(value: Value) -> GrpcValue {
                 TimeUnit::Microsecond => ValueData::DurationMicrosecondValue(v.value()),
                 TimeUnit::Nanosecond => ValueData::DurationNanosecondValue(v.value()),
             }),
-            Value::List(_) => unreachable!(),
+            Value::List(_) | Value::Decimal128(_) => unreachable!(),
         },
     }
 }

src/common/decimal/Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "decimal"
+name = "common-decimal"
 version.workspace = true
 edition.workspace = true
 license.workspace = true

src/common/decimal/src/decimal128.rs

@@ -43,23 +43,34 @@ const BYTES_TO_OVERFLOW_RUST_DECIMAL: usize = 28;
 /// **precision**: the total number of digits in the number, it's range is \[1, 38\].
 ///
 /// **scale**: the number of digits to the right of the decimal point, it's range is \[0, precision\].
-#[derive(Debug, Default, Eq, Copy, Clone, Serialize, Deserialize)]
+#[derive(Debug, Eq, Copy, Clone, Serialize, Deserialize)]
 pub struct Decimal128 {
     value: i128,
     precision: u8,
     scale: i8,
 }
 
 impl Decimal128 {
-    /// Create a new Decimal128 from i128, precision and scale.
-    pub fn new_unchecked(value: i128, precision: u8, scale: i8) -> Self {
+    /// Create a new Decimal128 from i128, precision and scale without any validation.
+    pub fn new(value: i128, precision: u8, scale: i8) -> Self {
+        // debug assert precision and scale is valid
+        debug_assert!(
+            precision > 0 && precision <= DECIMAL128_MAX_PRECISION,
+            "precision should be in [1, {}]",
+            DECIMAL128_MAX_PRECISION
+        );
+        debug_assert!(
+            scale >= 0 && scale <= precision as i8,
+            "scale should be in [0, precision]"
+        );
         Self {
             value,
             precision,
             scale,
         }
     }
 
+    /// Try new Decimal128 from i128, precision and scale with validation.
     pub fn try_new(value: i128, precision: u8, scale: i8) -> error::Result<Self> {
         // make sure the precision and scale is valid.
         valid_precision_and_scale(precision, scale)?;
@@ -70,6 +81,7 @@ impl Decimal128 {
         })
     }
 
+    /// Return underlying value without precision and scale
     pub fn val(&self) -> i128 {
         self.value
     }
@@ -90,6 +102,17 @@ impl Decimal128 {
     }
 }
 
+/// The default value of Decimal128 is 0, and its precision is 1 and scale is 0.
+impl Default for Decimal128 {
+    fn default() -> Self {
+        Self {
+            value: 0,
+            precision: 1,
+            scale: 0,
+        }
+    }
+}
+
 impl PartialEq for Decimal128 {
     fn eq(&self, other: &Self) -> bool {
         self.precision.eq(&other.precision)
@@ -270,7 +293,7 @@ mod tests {
 
     #[test]
     fn test_common_decimal128() {
-        let decimal = Decimal128::new_unchecked(123456789, 9, 3);
+        let decimal = Decimal128::new(123456789, 9, 3);
         assert_eq!(decimal.to_string(), "123456.789");
 
         let decimal = Decimal128::try_new(123456789, 9, 0);

src/common/decimal/src/lib.rs

@@ -14,3 +14,5 @@
 
 pub mod decimal128;
 pub mod error;
+
+pub use decimal128::Decimal128;

src/common/grpc/src/select.rs

@@ -71,7 +71,8 @@ macro_rules! convert_arrow_array_to_grpc_vals {
                     return Ok(vals);
                 },
             )+
-            ConcreteDataType::Null(_) | ConcreteDataType::List(_) | ConcreteDataType::Dictionary(_) => unreachable!("Should not send {:?} in gRPC", $data_type),
+            // TODO(QuenKar): support gRPC for Decimal128
+            ConcreteDataType::Null(_) | ConcreteDataType::List(_) | ConcreteDataType::Dictionary(_) | ConcreteDataType::Decimal128(_) => unreachable!("Should not send {:?} in gRPC", $data_type),
         }
     }};
 }

src/datatypes/Cargo.toml

@@ -13,6 +13,7 @@ arrow-array.workspace = true
 arrow-schema.workspace = true
 arrow.workspace = true
 common-base.workspace = true
+common-decimal.workspace = true
 common-error.workspace = true
 common-macro.workspace = true
 common-telemetry.workspace = true
@@ -23,6 +24,7 @@ num = "0.4"
 num-traits = "0.2"
 ordered-float = { version = "3.0", features = ["serde"] }
 paste = "1.0"
+rust_decimal = "1.32.0"
 serde.workspace = true
 serde_json = "1.0"
 snafu.workspace = true