update text

Signed-off-by: Konstantin Morozov <just.morozov.k@gmail.com>

Author: k-morozov

src/Storages/MergeTree/ExportPartitionUtils.cpp

@@ -710,19 +710,21 @@ namespace ExportPartitionUtils
             const ColumnWithTypeAndName & source_column,
             const ColumnWithTypeAndName & destination_column,
             size_t position,
-            const StorageID & destination_storage_id)
+            const StorageID & destination_storage_id,
+            bool match_by_name)
         {
             if (source_column.name != destination_column.name)
                 throw Exception(
                     ErrorCodes::BAD_ARGUMENTS,
                     "Cannot export to {}: partition key column '{}' is at position {} in the source "
                     "table, but the destination's column at that position is named '{}'. EXPORT "
-                    "PART/PARTITION matches columns by position, so partition key columns must be "
-                    "declared at the same position in both tables.",
+                    "PART/PARTITION {} so partition key columns must be declared {} in both tables.",
                     destination_storage_id.getFullTableName(),
                     source_column.name,
                     position,
-                    destination_column.name);
+                    destination_column.name,
+                    match_by_name ? "matches columns by name" : "matches columns by position",
+                    match_by_name ? "with the same name" : "at the same position");
 
             if (!haveSameTupleElementLayout(source_column.type, destination_column.type))
                 throw Exception(
@@ -885,15 +887,17 @@ namespace ExportPartitionUtils
                     continue;
 
                 verifyPartitionKeyColumn(
-                    source_columns[source_it->second], destination_column, source_it->second, destination_storage_id);
+                    source_columns[source_it->second], destination_column, source_it->second, destination_storage_id,
+                    /*match_by_name=*/ true);
             }
         }
         else
         {
             const size_t num_columns = std::min(source_columns.size(), destination_columns.size());
             for (size_t i = 0; i < num_columns; ++i)
                 if (partition_key_owner_columns.contains(source_columns[i].name))
-                    verifyPartitionKeyColumn(source_columns[i], destination_columns[i], i, destination_storage_id);
+                    verifyPartitionKeyColumn(source_columns[i], destination_columns[i], i, destination_storage_id,
+                        /*match_by_name=*/ false);
         }
 
         /// Lossy casts may silently change values, so reject them unless the user opts in.

src/Storages/MergeTree/MergeTreeData.cpp

@@ -6782,7 +6782,6 @@ void MergeTreeData::exportPartToTable(
 #endif
     }
 
-    /// Positional CAST matching, like `INSERT INTO dest SELECT * FROM src`.
     ExportPartitionUtils::verifyExportSchemaCastable(
         source_metadata_ptr, destination_metadata_ptr, dest_storage->getStorageID(), query_context);
 

src/Storages/StorageReplicatedMergeTree.cpp

@@ -8412,7 +8412,6 @@ void StorageReplicatedMergeTree::exportPartitionToTable(const PartitionCommand &
     auto src_snapshot = getInMemoryMetadataPtr();
     auto destination_snapshot = dest_storage->getInMemoryMetadataPtr();
 
-    /// Positional CAST matching, like `INSERT INTO dest SELECT * FROM src`.
     ExportPartitionUtils::verifyExportSchemaCastable(
         src_snapshot, destination_snapshot, dest_storage->getStorageID(), query_context);