XiaoHongbo-Hope opened a new issue, #283:
URL: https://github.com/apache/paimon-cpp/issues/283

   ### Motivation
   
   Java Paimon stores `MAP<K, BLOB>` columns in dedicated `.blob` files. Paimon 
C++ should be able to load those schemas and read the existing payload format 
through the Table API, including data-evolution fallback across sequence layers.
   
   ### Reader scope
   
   - Decode payload version 1 for BOOL, integer, DATE, STRING, BINARY, and 
DECIMAL keys.
   - Support both inline BLOB values and BLOB descriptors.
   - Preserve null maps, empty maps, null values, and empty values.
   - Validate payload bounds, duplicate keys, DECIMAL canonical encoding, UTF-8 
STRING keys, and non-null map keys required by Arrow.
   - Resolve placeholders across multiple sequence layers.
   
   `paimon.map.selected-keys` is intentionally unsupported for Map Blob reads 
for now because filtering the internal fallback placeholder would lose 
older-layer data. `TIME` keys and `ARRAY<BLOB>` are also outside this issue and 
should be handled separately with their end-to-end type/format support.
   
   ### Write support
   
   This issue only tracks read compatibility. C++ table creation, regular 
writes, and append compaction must reject `MAP<K, BLOB>` until a 
Java-compatible Map Blob writer is implemented. There is no concrete writer 
timeline yet; writer support should be proposed and tracked separately.
   
   Implementation: #278


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