fix: fix decimal bug (#557)

* fix decimal bug

* fix decimal bug

Author: sundy-li

.github/workflows/ttc.yml

@@ -10,6 +10,7 @@ on:
       - 'core/**'
       - 'driver/**'
       - 'ttc/**'
+      - 'sql/**'
 
 jobs:
   docker:

cli/tests/00-base.result

@@ -14,6 +14,7 @@ with comment
 "
 a"
 3
+-9999999999999999999999999999999999999999999999999999999999999999999999999999
 1
 NULL
 3.00	3.00	0.0000000170141183460469231731687303715884105727000	-0.0000000170141183460469231731687303715884105727000

cli/tests/00-base.sql

@@ -19,6 +19,8 @@ select /* ignore this block */ 'with comment';
 select 1; select 2; select '
 a'; select 3;
 
+select -9999999999999999999999999999999999999999999999999999999999999999999999999999;
+
 -- issue 409
 drop table if exists t;
 create table t(id tuple(STRING, array(tuple(array(int), array(STRING NOT NULL)))));

sql/src/value.rs

@@ -980,6 +980,14 @@ pub fn display_decimal_256(num: i256, scale: u8) -> String {
 pub fn parse_decimal(text: &str, size: DecimalSize) -> Result<NumberValue> {
     let mut start = 0;
     let bytes = text.as_bytes();
+    let mut is_negative = false;
+
+    // Check if the number is negative
+    if bytes[start] == b'-' {
+        is_negative = true;
+        start += 1;
+    }
+
     while start < text.len() && bytes[start] == b'0' {
         start += 1
     }
@@ -1016,13 +1024,21 @@ pub fn parse_decimal(text: &str, size: DecimalSize) -> Result<NumberValue> {
         let precision = std::cmp::min(digits.len(), 76);
         let digits = unsafe { std::str::from_utf8_unchecked(&digits[..precision]) };
 
-        if size.precision > 38 {
-            Ok(NumberValue::Decimal256(
-                i256::from_string(digits).unwrap(),
-                size,
-            ))
+        let result = if size.precision > 38 {
+            NumberValue::Decimal256(i256::from_string(digits).unwrap(), size)
+        } else {
+            NumberValue::Decimal128(digits.parse::<i128>()?, size)
+        };
+
+        // If the number was negative, negate the result
+        if is_negative {
+            match result {
+                NumberValue::Decimal256(val, size) => Ok(NumberValue::Decimal256(-val, size)),
+                NumberValue::Decimal128(val, size) => Ok(NumberValue::Decimal128(-val, size)),
+                _ => Ok(result),
+            }
         } else {
-            Ok(NumberValue::Decimal128(digits.parse::<i128>()?, size))
+            Ok(result)
         }
     }
 }

ttc/Cargo.toml

@@ -13,7 +13,7 @@ repository = { workspace = true }
 [dependencies]
 bytes = "1"
 clap = { version = "4.4", features = ["derive", "env"] }
-databend-driver = { path = "../driver" }
+databend-driver = { workspace = true }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = { version = "1.0", default-features = false, features = ["std"] }
 tokio = { version = "1.34", features = [