[Bug] Fix core when modifing char to varchar and loading boolean with…

… replace aggregation (#4042)

1. Doris support modify char to varchar. There is a bug when use two-level pointer when converting the date.
2. Boolean can be used as metric value with REPLACE and REPLACE_IF_NOT_NULL aggregation function. The aggregation function should be added into aggregation map.

be/src/olap/aggregate_func.cpp

@@ -114,6 +114,7 @@ AggregateFuncResolver::AggregateFuncResolver() {
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_SUM, OLAP_FIELD_TYPE_DECIMAL>();
 
     // Replace Aggregate Function
+    add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE, OLAP_FIELD_TYPE_BOOL>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE, OLAP_FIELD_TYPE_TINYINT>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE, OLAP_FIELD_TYPE_SMALLINT>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE, OLAP_FIELD_TYPE_INT>();
@@ -128,6 +129,7 @@ AggregateFuncResolver::AggregateFuncResolver() {
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE, OLAP_FIELD_TYPE_VARCHAR>();
 
     // ReplaceIfNotNull Aggregate Function
+    add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE_IF_NOT_NULL, OLAP_FIELD_TYPE_BOOL>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE_IF_NOT_NULL, OLAP_FIELD_TYPE_TINYINT>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE_IF_NOT_NULL, OLAP_FIELD_TYPE_SMALLINT>();
     add_aggregate_mapping<OLAP_FIELD_AGGREGATION_REPLACE_IF_NOT_NULL, OLAP_FIELD_TYPE_INT>();

be/src/olap/schema_change.cpp

@@ -334,7 +334,7 @@ bool RowBlockChanger::change_row_block(
                             p--;
                         }
                         slice->size = p + 1;
-                        write_helper.set_field_content(i, reinterpret_cast<char*>(&slice), mem_pool);
+                        write_helper.set_field_content(i, reinterpret_cast<char*>(slice), mem_pool);
                     }
                 }
             } else if ((reftype == OLAP_FIELD_TYPE_FLOAT && newtype == OLAP_FIELD_TYPE_DOUBLE)