Small progress on alter rename

dbms/src/Access/AccessType.h

@@ -28,7 +28,6 @@ enum class AccessType
     ADD_COLUMN,
     DROP_COLUMN,
     MODIFY_COLUMN,
-    RENAME_COLUMN,
     COMMENT_COLUMN,
     CLEAR_COLUMN,
     ALTER_COLUMN,       /// allow to execute ALTER {ADD|DROP|MODIFY...} COLUMN
@@ -196,7 +195,6 @@ namespace impl
             ACCESS_TYPE_TO_KEYWORD_CASE(ADD_COLUMN);
             ACCESS_TYPE_TO_KEYWORD_CASE(DROP_COLUMN);
             ACCESS_TYPE_TO_KEYWORD_CASE(MODIFY_COLUMN);
-            ACCESS_TYPE_TO_KEYWORD_CASE(RENAME_COLUMN);
             ACCESS_TYPE_TO_KEYWORD_CASE(COMMENT_COLUMN);
             ACCESS_TYPE_TO_KEYWORD_CASE(CLEAR_COLUMN);
             ACCESS_TYPE_TO_KEYWORD_CASE(ALTER_COLUMN);

dbms/src/Interpreters/InterpreterAlterQuery.cpp

@@ -282,7 +282,6 @@ AccessRightsElements InterpreterAlterQuery::getRequiredAccessForCommand(const AS
         }
         case ASTAlterCommand::RENAME_COLUMN:
         {
-            required_access.emplace_back(AccessType::RENAME_COLUMN, database, table);
             break;
         }
         case ASTAlterCommand::NO_TYPE: break;

dbms/src/Parsers/ParserAlterQuery.cpp

@@ -27,6 +27,7 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
     ParserKeyword s_drop_column("DROP COLUMN");
     ParserKeyword s_clear_column("CLEAR COLUMN");
     ParserKeyword s_modify_column("MODIFY COLUMN");
+    ParserKeyword s_rename_column("RENAME COLUMN");
     ParserKeyword s_comment_column("COMMENT COLUMN");
     ParserKeyword s_modify_order_by("MODIFY ORDER BY");
     ParserKeyword s_modify_ttl("MODIFY TTL");
@@ -77,6 +78,7 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
     ParserKeyword s_delete_where("DELETE WHERE");
     ParserKeyword s_update("UPDATE");
     ParserKeyword s_where("WHERE");
+    ParserKeyword s_to("TO");
 
     ParserCompoundIdentifier parser_name;
     ParserStringLiteral parser_string_literal;
@@ -121,6 +123,22 @@ bool ParserAlterCommand::parseImpl(Pos & pos, ASTPtr & node, Expected & expected
 
             command->type = ASTAlterCommand::ADD_COLUMN;
         }
+        else if (s_rename_column.ignore(pos, expected))
+        {
+            if (s_if_not_exists.ignore(pos, expected))
+                command->if_not_exists = true;
+
+            if (!parser_name.parse(pos, command->column, expected))
+                return false;
+
+            if (!s_to.ignore(pos, expected))
+                return false;
+
+            if (!parser_name.parse(pos, command->rename_to, expected))
+                return false;
+
+            command->type = ASTAlterCommand::RENAME_COLUMN;
+        }
         else if (s_drop_partition.ignore(pos, expected))
         {
             if (!parser_partition.parse(pos, command->partition, expected))

dbms/src/Parsers/ParserAlterQuery.h

@@ -12,6 +12,7 @@ namespace DB
   *     [DROP COLUMN [IF EXISTS] col_to_drop, ...]
   *     [CLEAR COLUMN [IF EXISTS] col_to_clear [IN PARTITION partition],]
   *     [MODIFY COLUMN [IF EXISTS] col_to_modify type, ...]
+  *     [RENAME COLUMN [IF EXISTS] col_name TO col_name]
   *     [MODIFY PRIMARY KEY (a, b, c...)]
   *     [MODIFY SETTING setting_name=setting_value, ...]
   *     [COMMENT COLUMN [IF EXISTS] col_name string]

dbms/src/Storages/AlterCommands.cpp

@@ -533,7 +533,7 @@ bool AlterCommand::isRequireMutationStage(const StorageInMemoryMetadata & metada
     if (ignore)
         return false;
 
-    if (type == DROP_COLUMN || type == DROP_INDEX || type == RENAME_COLUMN)
+    if (type == DROP_COLUMN || type == DROP_INDEX)
         return true;
 
     if (type != MODIFY_COLUMN || data_type == nullptr)

dbms/src/Storages/ColumnsDescription.cpp

@@ -199,23 +199,14 @@ void ColumnsDescription::remove(const String & column_name)
 
 void ColumnsDescription::rename(const String & column_from, const String & column_to)
 {
-    auto range = getNameRange(columns, column_from);
+    auto it = columns.get<1>().find(column_from);
+    if (it == columns.get<1>().end())
+        throw Exception("Cannot find column " + column_from + " in ColumnsDescription", ErrorCodes::LOGICAL_ERROR);
 
-    if (range.first == range.second)
-        throw Exception("There is no column " + column_from + " in table.", ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
-
-    std::vector<ColumnDescription> iterators;
-    for (auto list_it = range.first; list_it != range.second;)
+    columns.get<1>().modify_key(it, [&column_to] (String & old_name)
     {
-        iterators.push_back(*list_it);
-        list_it = columns.get<0>().erase(list_it);
-    }
-
-    for (auto & col_desc : iterators)
-    {
-        boost::replace_all(col_desc.name, column_from, column_to);
-        add(col_desc);
-    }
+        old_name = column_to;
+    });
 }
 
 

dbms/src/Storages/MergeTree/IMergeTreeReader.cpp

@@ -30,6 +30,7 @@ IMergeTreeReader::IMergeTreeReader(const MergeTreeData::DataPartPtr & data_part_
     , columns(columns_), uncompressed_cache(uncompressed_cache_), mark_cache(mark_cache_)
     , settings(settings_), storage(data_part_->storage)
     , all_mark_ranges(all_mark_ranges_)
+    , alter_conversions(storage.getAlterConversionsForPart(data_part))
 {
 }
 
@@ -62,6 +63,11 @@ static bool arrayHasNoElementsRead(const IColumn & column)
 }
 
 
+//void IMergeTreeReader::renameColumnsWithAlters(Columns & res_columns)
+//{
+//
+//}
+
 void IMergeTreeReader::fillMissingColumns(Columns & res_columns, bool & should_evaluate_missing_defaults, size_t num_rows)
 {
     try

dbms/src/Storages/MergeTree/IMergeTreeReader.h

@@ -48,6 +48,9 @@ public:
     /// try to perform conversions of columns.
     void performRequiredConversions(Columns & res_columns);
 
+    /// TODO(alesap)
+    void renameColumnsWithAlters(Columns & res_columns);
+
     const NamesAndTypesList & getColumns() const { return columns; }
     size_t numColumnsInResult() const { return columns.size(); }
 
@@ -78,6 +81,7 @@ protected:
     MarkRanges all_mark_ranges;
 
     friend class MergeTreeRangeReader::DelayedStream;
+    MergeTreeData::AlterConversions alter_conversions;
 };
 
 }

dbms/src/Storages/MergeTree/MergeTreeData.cpp

@@ -3589,8 +3589,15 @@ bool MergeTreeData::canUsePolymorphicParts(const MergeTreeSettings & settings, S
     return true;
 }
 
-MergeTreeData::AlterConversions MergeTreeData::getAlterConversionsForPart(const MergeTreeDataPartPtr /*part*/) const
+MergeTreeData::AlterConversions MergeTreeData::getAlterConversionsForPart(const MergeTreeDataPartPtr part) const
 {
-    return AlterConversions{};
+    MutationCommands commands = getFirtsAlterMutationCommandsForPart(part);
+
+    AlterConversions result{};
+    for (const auto & command : commands)
+        if (command.type == MutationCommand::Type::RENAME_COLUMN)
+            result.rename_map[command.column_name] = command.rename_to;
+
+    return result;
 }
 }

dbms/src/Storages/MutationCommands.cpp

@@ -94,6 +94,15 @@ std::optional<MutationCommand> MutationCommand::parse(ASTAlterCommand * command,
             res.clear = true;
         return res;
     }
+    else if (parse_alter_commands && command->type == ASTAlterCommand::RENAME_COLUMN)
+    {
+        MutationCommand res;
+        res.ast = command->ptr();
+        res.type = MutationCommand::Type::RENAME_COLUMN;
+        res.column_name = command->column->as<ASTIdentifier &>().name;
+        res.rename_to = command->rename_to->as<ASTIdentifier &>().name;
+        return res;
+    }
     else if (command->type == ASTAlterCommand::MATERIALIZE_TTL)
     {
         MutationCommand res;

dbms/src/Storages/MutationCommands.h

@@ -31,7 +31,8 @@ struct MutationCommand
         READ_COLUMN,
         DROP_COLUMN,
         DROP_INDEX,
-        MATERIALIZE_TTL
+        MATERIALIZE_TTL,
+        RENAME_COLUMN,
     };
 
     Type type = EMPTY;
@@ -53,6 +54,9 @@ struct MutationCommand
     /// We need just clear column, not drop from metadata.
     bool clear = false;
 
+    /// Column rename_to
+    String rename_to;
+
     /// If parse_alter_commands, than consider more Alter commands as mutation commands
     static std::optional<MutationCommand> parse(ASTAlterCommand * command, bool parse_alter_commands = false);
 };

dbms/tests/queries/0_stateless/01213_alter_rename_column.reference

@@ -0,0 +1,2 @@
+1
+1

dbms/tests/queries/0_stateless/01213_alter_rename_column.sql

@@ -0,0 +1,23 @@
+DROP TABLE IF EXISTS table_for_rename;
+
+CREATE TABLE table_for_rename
+(
+  date Date,
+  key UInt64,
+  value1 String,
+  value2 String,
+  value3 String
+)
+ENGINE = MergeTree()
+PARTITION BY date
+ORDER BY key;
+
+INSERT INTO table_for_rename SELECT toDate('2019-10-01') + number % 3, number, toString(number), toString(number), toString(number) from numbers(9);
+
+SELECT value1 FROM table_for_rename WHERE key = 1;
+
+ALTER TABLE table_for_rename RENAME COLUMN value1 to renamed_value1;
+
+SELECT renamed_value1 FROM table_for_rename WHERE key = 1;
+
+DROP TABLE IF EXISTS table_for_rename;