First attempt to fix issue ClickHouse#7878

filimonov · Feb 4, 2020 · 8bbd883 · 8bbd883
1 parent 619fc2e
commit 8bbd883
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Showing 5 changed files with 51 additions and 4 deletions.
diff --git a/dbms/src/DataStreams/ConvertingBlockInputStream.cpp b/dbms/src/DataStreams/ConvertingBlockInputStream.cpp
@@ -4,7 +4,7 @@
 #include <Common/assert_cast.h>
 #include <Common/quoteString.h>
 #include <Parsers/IAST.h>
-
+#include <iostream>
 
 namespace DB
 {
@@ -65,8 +65,20 @@ ConvertingBlockInputStream::ConvertingBlockInputStream(
                     throw Exception("Cannot find column " + backQuote(res_elem.name) + " in source stream",
                         ErrorCodes::THERE_IS_NO_COLUMN);
                 break;
+
+            case MatchColumnsMode::NameOrDefault:
+                if (input_header.has(res_elem.name))
+                    conversion[result_col_num] = input_header.getPositionByName(res_elem.name);
+		else {
+		    std::cerr << "column " << result_col_num << " will be set to default\n";	
+                    conversion[result_col_num] = USE_DEFAULT;
+		}
+		break;
         }
 
+	if (conversion[result_col_num] == USE_DEFAULT)
+	    continue;
+
         const auto & src_elem = input_header.getByPosition(conversion[result_col_num]);
 
         /// Check constants.
@@ -100,9 +112,18 @@ Block ConvertingBlockInputStream::readImpl()
     Block res = header.cloneEmpty();
     for (size_t res_pos = 0, size = conversion.size(); res_pos < size; ++res_pos)
     {
-        const auto & src_elem = src.getByPosition(conversion[res_pos]);
         auto & res_elem = res.getByPosition(res_pos);
 
+        if (conversion[res_pos] == USE_DEFAULT)
+	{
+	    // Create a column with default values
+	    auto column_with_defaults = res_elem.type->createColumn()->cloneResized(src.rows());
+	    res_elem.column = std::move(column_with_defaults);
+	    continue;
+        }
+
+	const auto & src_elem = src.getByPosition(conversion[res_pos]);
+
         ColumnPtr converted = castColumnWithDiagnostic(src_elem, res_elem, context);
 
         if (isColumnConst(*src_elem.column) && !isColumnConst(*res_elem.column))

diff --git a/dbms/src/DataStreams/ConvertingBlockInputStream.h b/dbms/src/DataStreams/ConvertingBlockInputStream.h
@@ -28,7 +28,9 @@ class ConvertingBlockInputStream : public IBlockInputStream
         /// Require same number of columns in source and result. Match columns by corresponding positions, regardless to names.
         Position,
         /// Find columns in source by their names. Allow excessive columns in source.
-        Name
+        Name,
+        /// Find columns in source by their names if present else use the default. Allow excessive columns in source.
+	NameOrDefault
     };
 
     ConvertingBlockInputStream(
@@ -48,6 +50,7 @@ class ConvertingBlockInputStream : public IBlockInputStream
 
     /// How to construct result block. Position in source block, where to get each column.
     using Conversion = std::vector<size_t>;
+    const size_t USE_DEFAULT = static_cast<size_t>(-1);
     Conversion conversion;
 };
 

diff --git a/dbms/src/DataStreams/PushingToViewsBlockOutputStream.cpp b/dbms/src/DataStreams/PushingToViewsBlockOutputStream.cpp
@@ -233,7 +233,7 @@ void PushingToViewsBlockOutputStream::process(const Block & block, size_t view_n
             /// and two-level aggregation is triggered).
             in = std::make_shared<SquashingBlockInputStream>(
                     in, context.getSettingsRef().min_insert_block_size_rows, context.getSettingsRef().min_insert_block_size_bytes);
-            in = std::make_shared<ConvertingBlockInputStream>(context, in, view.out->getHeader(), ConvertingBlockInputStream::MatchColumnsMode::Name);
+            in = std::make_shared<ConvertingBlockInputStream>(context, in, view.out->getHeader(), ConvertingBlockInputStream::MatchColumnsMode::NameOrDefault);
         }
         else
             in = std::make_shared<OneBlockInputStream>(block);

diff --git a/dbms/tests/queries/0_stateless/01069_materialized_view_alter_target_table.reference b/dbms/tests/queries/0_stateless/01069_materialized_view_alter_target_table.reference
@@ -0,0 +1,8 @@
+1
+1
+2
+3
+1	0
+1	0
+2	0
+3	0
diff --git a/dbms/tests/queries/0_stateless/01069_materialized_view_alter_target_table.sql b/dbms/tests/queries/0_stateless/01069_materialized_view_alter_target_table.sql
@@ -0,0 +1,15 @@
+DROP TABLE IF EXISTS mv_source;
+DROP TABLE IF EXISTS mv_target;
+
+CREATE TABLE mv_source (`a` UInt64) ENGINE = MergeTree ORDER BY tuple();
+CREATE TABLE mv_target (`a` UInt64) ENGINE = MergeTree ORDER BY tuple();
+
+CREATE MATERIALIZED VIEW mv TO mv_target AS SELECT * FROM mv_source;
+
+INSERT INTO mv_source VALUES (1);
+
+ALTER TABLE mv_target ADD COLUMN b UInt8;
+INSERT INTO mv_source VALUES (1),(2),(3);
+
+SELECT * FROM mv ORDER BY a;
+SELECT * FROM mv_target ORDER BY a;