From ef8781cce77dddff57f44aaa1005b0f88e30dcdf Mon Sep 17 00:00:00 2001
From: alesapin <alesapin@gmail.com>
Date: Wed, 17 Jun 2020 17:37:21 +0300
Subject: [PATCH] Better getVirtuals method

---
 src/Storages/IStorage.cpp           | 4 ++--
 src/Storages/IStorage.h             | 2 +-
 src/Storages/StorageDistributed.cpp | 4 ++--
 src/Storages/StorageMerge.cpp       | 2 +-
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/Storages/IStorage.cpp b/src/Storages/IStorage.cpp
index 38fdaa832bd..884982c93b9 100644
--- a/src/Storages/IStorage.cpp
+++ b/src/Storages/IStorage.cpp
@@ -38,10 +38,10 @@ const ColumnsDescription & IStorage::getColumns() const
 }
 
 
-bool IStorage::isVirtualColumn(const String & column_name) const
+bool IStorage::isVirtualColumn(const String & column_name, const StorageMetadataPtr & metadata_snapshot) const
 {
     /// Virtual column maybe overriden by real column
-    return !getColumns().has(column_name) && getVirtuals().contains(column_name);
+    return !metadata_snapshot->getColumns().has(column_name) && getVirtuals().contains(column_name);
 }
 
 RWLockImpl::LockHolder IStorage::tryLockTimed(
diff --git a/src/Storages/IStorage.h b/src/Storages/IStorage.h
index bb4bf2ed09b..a125c6f8310 100644
--- a/src/Storages/IStorage.h
+++ b/src/Storages/IStorage.h
@@ -159,7 +159,7 @@ protected:
 
     /// Returns whether the column is virtual - by default all columns are real.
     /// Initially reserved virtual column name may be shadowed by real column.
-    bool isVirtualColumn(const String & column_name) const;
+    bool isVirtualColumn(const String & column_name, const StorageMetadataPtr & metadata_snapshot) const;
 
 
 private:
diff --git a/src/Storages/StorageDistributed.cpp b/src/Storages/StorageDistributed.cpp
index 6868f468f2e..ce4fcbb3513 100644
--- a/src/Storages/StorageDistributed.cpp
+++ b/src/Storages/StorageDistributed.cpp
@@ -464,7 +464,7 @@ QueryProcessingStage::Enum StorageDistributed::getQueryProcessingStage(const Con
 
 Pipes StorageDistributed::read(
     const Names & column_names,
-    const StorageMetadataPtr & /*metadata_snapshot*/,
+    const StorageMetadataPtr & metadata_snapshot,
     const SelectQueryInfo & query_info,
     const Context & context,
     QueryProcessingStage::Enum processed_stage,
@@ -497,7 +497,7 @@ Pipes StorageDistributed::read(
     const Scalars & scalars = context.hasQueryContext() ? context.getQueryContext().getScalars() : Scalars{};
 
     bool has_virtual_shard_num_column = std::find(column_names.begin(), column_names.end(), "_shard_num") != column_names.end();
-    if (has_virtual_shard_num_column && !isVirtualColumn("_shard_num"))
+    if (has_virtual_shard_num_column && !isVirtualColumn("_shard_num", metadata_snapshot))
         has_virtual_shard_num_column = false;
 
     ClusterProxy::SelectStreamFactory select_stream_factory = remote_table_function_ptr
diff --git a/src/Storages/StorageMerge.cpp b/src/Storages/StorageMerge.cpp
index 9765db35fc3..92e965c420e 100644
--- a/src/Storages/StorageMerge.cpp
+++ b/src/Storages/StorageMerge.cpp
@@ -146,7 +146,7 @@ Pipes StorageMerge::read(
 
     for (const auto & column_name : column_names)
     {
-        if (column_name == "_table" && isVirtualColumn(column_name))
+        if (column_name == "_table" && isVirtualColumn(column_name, metadata_snapshot))
             has_table_virtual_column = true;
         else
             real_column_names.push_back(column_name);