reinitialize primary key after ALTER [#CLICKHOUSE-2853]

dbms/include/DB/Storages/MergeTree/MergeTreeData.h

@@ -474,6 +474,7 @@ public:
 private:
 	friend struct MergeTreeDataPart;
 	friend class StorageMergeTree;
+	friend class ReplicatedMergeTreeAlterThread;
 	friend class MergeTreeDataMerger;
 
 	bool require_part_metadata;

dbms/src/Storages/MergeTree/MergeTreeData.cpp

@@ -109,14 +109,14 @@ MergeTreeData::MergeTreeData(
 
 	merging_params.check(*columns);
 
+	if (!primary_expr_ast && merging_params.mode != MergingParams::Unsorted)
+		throw Exception("Primary key could be empty only for UnsortedMergeTree", ErrorCodes::BAD_ARGUMENTS);
+
+	initPrimaryKey();
+
 	/// Creating directories, if not exist.
 	Poco::File(full_path).createDirectories();
 	Poco::File(full_path + "detached").createDirectory();
-
-	if (primary_expr_ast)
-		initPrimaryKey();
-	else if (merging_params.mode != MergingParams::Unsorted)
-		throw Exception("Primary key could be empty only for UnsortedMergeTree", ErrorCodes::BAD_ARGUMENTS);
 }
 
 
@@ -143,6 +143,9 @@ void MergeTreeData::checkNoMultidimensionalArrays(const NamesAndTypesList & colu
 
 void MergeTreeData::initPrimaryKey()
 {
+	if (!primary_expr_ast)
+		return;
+
 	/// Initialize description of sorting.
 	sort_descr.clear();
 	sort_descr.reserve(primary_expr_ast->children.size());

dbms/src/Storages/MergeTree/ReplicatedMergeTreeAlterThread.cpp

@@ -129,6 +129,11 @@ void ReplicatedMergeTreeAlterThread::run()
 							storage.data.column_defaults = std::move(column_defaults);
 						}
 
+						/// Reinitialize primary key because primary key column types might have changed.
+						storage.data.initPrimaryKey();
+						if (storage.unreplicated_data)
+							storage.unreplicated_data->initPrimaryKey();
+
 						LOG_INFO(log, "Applied changes to table.");
 					}
 					else

dbms/src/Storages/StorageMergeTree.cpp

@@ -233,8 +233,9 @@ void StorageMergeTree::alter(
 	if (primary_key_is_modified)
 	{
 		data.primary_expr_ast = new_primary_key_ast;
-		data.initPrimaryKey();
 	}
+	/// Reinitialize primary key because primary key column types might have changed.
+	data.initPrimaryKey();
 
 	for (auto & transaction : transactions)
 		transaction->commit();

dbms/tests/queries/0_stateless/00427_alter_primary_key.reference

 query failed
 query failed
+2017-02-09
 foo	1486598400	1
 bar	1486598400	1

dbms/tests/queries/0_stateless/00427_alter_primary_key.sh

@@ -28,6 +28,8 @@ perform "ALTER TABLE test.alter MODIFY COLUMN c UInt32"
 
 perform "INSERT INTO test.alter VALUES ('2017-02-09', 'bar', 1486598400, '2017-02-09 00:00:00')"
 
+perform "SELECT d FROM test.alter WHERE a = 'bar'"
+
 perform "SELECT a, b, b = toUnixTimestamp(c) FROM test.alter ORDER BY a FORMAT TSV"
 
 perform "DROP TABLE test.alter"