fix: add compatibility for reading non-standard decimal256 format

src/query/storages/common/table_meta/src/meta/mod.rs

@@ -37,6 +37,7 @@ pub use statistics::*;
 // export legacy versioned table meta types locally,
 // currently, used by versioned readers only
 pub(crate) use testing::*;
+pub use utils::is_possible_non_standard_decimal_block;
 pub use utils::parse_storage_prefix;
 pub use utils::trim_vacuum2_object_prefix;
 pub use utils::try_extract_uuid_str_from_path;

src/query/storages/common/table_meta/src/meta/utils.rs

@@ -83,7 +83,27 @@ pub fn parse_storage_prefix(options: &BTreeMap<String, String>, table_id: u64) -
 
 #[inline]
 pub fn trim_vacuum2_object_prefix(key: &str) -> &str {
-    key.strip_prefix(VACUUM2_OBJECT_KEY_PREFIX).unwrap_or(key)
+    // if object key (the file_name/stem part only) starts with a char which is larger or equals to
+    // VACUUM2_OBJECT_KEY_PREFIX( i.e. char 'g'), strip it off
+    if key >= VACUUM2_OBJECT_KEY_PREFIX {
+        &key[1..]
+    } else {
+        key
+    }
+}
+
+pub fn is_possible_non_standard_decimal_block(block_full_path: &str) -> Result<bool> {
+    let file_name = Path::new(block_full_path)
+        .file_name()
+        .ok_or_else(|| {
+            ErrorCode::StorageOther(format!(
+                "Illegal block path, no file name found: {}",
+                block_full_path
+            ))
+        })?
+        .to_str()
+        .expect("File stem of a block full path should always be valid UTF-8");
+    Ok(file_name < VACUUM2_OBJECT_KEY_PREFIX)
 }
 
 // Extracts the UUID part from the object key.
@@ -144,4 +164,26 @@ mod tests {
             assert_eq!(try_extract_uuid_str_from_path(input).unwrap(), expected);
         }
     }
+
+    #[test]
+    fn test_is_possible_non_standard_decimal_block() {
+        let test_cases = vec![
+            (
+                // stem of block path starts with 'g', should not contain non-standard decimals
+                "bucket/root/115/122/_b/g0191114d30fd78b89fae8e5c88327725_v2.parquet",
+                false,
+            ),
+            (
+                "bucket/root/115/122/_b/0191114d30fd78b89fae8e5c88327725_v2.parquet",
+                true,
+            ),
+        ];
+
+        for (input, expected) in test_cases {
+            assert_eq!(
+                is_possible_non_standard_decimal_block(input).unwrap(),
+                expected
+            );
+        }
+    }
 }

src/query/storages/fuse/src/io/locations.rs

@@ -81,7 +81,7 @@ impl TableMetaLocationGenerator {
     pub fn gen_block_location(&self) -> (Location, Uuid) {
         let part_uuid = Uuid::new_v4();
         let location_path = format!(
-            "{}/{}/{}{}_v{}.parquet",
+            "{}/{}/g{}{}_v{}.parquet",
             &self.prefix,
             FUSE_TBL_BLOCK_PREFIX,
             &self.part_prefix,