Merge pull request #300 from Enmk/deprecate_LowCardinalitySerializationAdaptor

Minor: Deprecated LowCardinalitySerializationAdaptor

Author: Enmk

clickhouse/columns/lowcardinalityadaptor.h

@@ -22,7 +22,9 @@ class CodedInputStream;
  * @see ClientOptions, CreateColumnByType
  */
 template <typename AdaptedColumnType>
-class LowCardinalitySerializationAdaptor : public AdaptedColumnType
+class
+[[deprecated("Makes implementation of LC(X) harder and code uglier. Will be removed in next major release (3.0) ")]]
+LowCardinalitySerializationAdaptor : public AdaptedColumnType
 {
 public:
     using AdaptedColumnType::AdaptedColumnType;