Cosmetics

src/Storages/MergeTree/MutateTask.cpp

@@ -76,8 +76,8 @@ static void splitAndModifyMutationCommands(
         {
             if (command.type == MutationCommand::Type::MATERIALIZE_COLUMN)
             {
-                /// For ordinary column with default expression, materialize column should not override past values
+                /// For ordinary column with default or materialized expression, MATERIALIZE COLUMN should not override past values
-                /// So we only mutated column if `command.column_name` is a materialized column or if the part does not have physical column file
+                /// So we only mutate column if `command.column_name` is a default/materialized column or if the part does not have physical column file
                 auto column_ordinary = table_columns.getOrdinary().tryGetByName(command.column_name);
                 if (!column_ordinary || !part->tryGetColumn(command.column_name) || !part->hasColumnFiles(*column_ordinary))
                 {
@@ -206,8 +206,8 @@ static void splitAndModifyMutationCommands(
         {
             if (command.type == MutationCommand::Type::MATERIALIZE_COLUMN)
             {
-                /// For ordinary column with default expression, materialize column should not override past values
+                /// For ordinary column with default or materialized expression, MATERIALIZE COLUMN should not override past values
-                /// So we only mutated column if `command.column_name` is a materialized column or if the part does not have physical column file
+                /// So we only mutate column if `command.column_name` is a default/materialized column or if the part does not have physical column file
                 auto column_ordinary = table_columns.getOrdinary().tryGetByName(command.column_name);
                 if (!column_ordinary || !part->tryGetColumn(command.column_name) || !part->hasColumnFiles(*column_ordinary))
                     for_interpreter.push_back(command);

tests/queries/0_stateless/02946_materialize_column_must_not_override_past_values.reference

@@ -0,0 +1,33 @@
+-- Compact parts
+Origin
+1	2
+2	54321
+After materialize
+1	2
+2	54321
+-- Wide parts
+Origin
+1	2
+2	54321
+After materialize
+1	2
+2	54321
+-- Nullable column != physically absent
+Origin
+1	2
+2	\N
+3	54321
+After materialize
+1	2
+2	\N
+3	54321
+-- Parts with renamed column
+Origin
+1	2
+2	54321
+After rename
+1	2
+2	54321
+After materialize
+1	2
+2	54321

tests/queries/0_stateless/02946_materialize_column_must_not_override_past_values.sql

@@ -0,0 +1,53 @@
+SET mutations_sync = 2;
+
+SELECT '-- Compact parts';
+
+CREATE TABLE tab (id Int64, dflt Int64 DEFAULT 54321) ENGINE MergeTree ORDER BY id;
+INSERT INTO tab (id, dflt) VALUES (1, 2);
+INSERT INTO tab (id) VALUES (2);
+SELECT 'Origin';
+SELECT * FROM tab ORDER BY id;
+ALTER TABLE tab MATERIALIZE COLUMN dflt;
+SELECT 'After materialize';
+SELECT * FROM tab ORDER BY id;
+DROP TABLE tab;
+
+SELECT '-- Wide parts';
+
+CREATE TABLE tab (id Int64, dflt Int64 DEFAULT 54321) ENGINE MergeTree ORDER BY id SETTINGS min_bytes_for_wide_part = 1;
+INSERT INTO tab (id, dflt) VALUES (1, 2);
+INSERT INTO tab (id) VALUES (2);
+SELECT 'Origin';
+SELECT * FROM tab ORDER BY id;
+ALTER TABLE tab MATERIALIZE COLUMN dflt;
+SELECT 'After materialize';
+SELECT * FROM tab ORDER BY id;
+DROP TABLE tab;
+
+SELECT '-- Nullable column != physically absent';
+
+CREATE TABLE tab (id Int64, dflt Nullable(Int64) DEFAULT 54321) ENGINE MergeTree ORDER BY id SETTINGS min_bytes_for_wide_part = 1;
+INSERT INTO tab (id, dflt) VALUES (1, 2);
+INSERT INTO tab (id, dflt) VALUES (2, NULL);
+INSERT INTO tab (id) VALUES (3);
+SELECT 'Origin';
+SELECT * FROM tab ORDER BY id;
+ALTER TABLE tab MATERIALIZE COLUMN dflt;
+SELECT 'After materialize';
+SELECT * FROM tab ORDER BY id;
+DROP TABLE tab;
+
+SELECT '-- Parts with renamed column';
+
+CREATE TABLE tab (id Int64, dflt Int64 DEFAULT 54321) ENGINE MergeTree ORDER BY id;
+INSERT INTO tab (id, dflt) VALUES (1, 2);
+INSERT INTO tab (id) VALUES (2);
+SELECT 'Origin';
+SELECT * FROM tab ORDER BY id;
+ALTER TABLE tab RENAME COLUMN dflt TO dflt2;
+SELECT 'After rename';
+SELECT * FROM tab ORDER BY id;
+ALTER TABLE tab MATERIALIZE COLUMN bar;
+SELECT 'After materialize';
+SELECT * FROM tab ORDER BY id;
+DROP TABLE tab;

tests/queries/0_stateless/02946_materialize_column_not_override_past_values.reference

@@ -1,29 +0,0 @@
---Origin--
-1	2
-2	54321
---After materialize--
-1	2
-2	54321
---Origin--
-1	2
-2	54321
---After materialize--
-1	2
-2	54321
---Origin--
-1	2
-2	\N
-3	54321
---After materialize--
-1	2
-2	\N
-3	54321
---Origin--
-1	2
-2	54321
---After rename--
-1	2
-2	54321
---After materialize--
-1	2
-2	54321

tests/queries/0_stateless/02946_materialize_column_not_override_past_values.sql

@@ -1,49 +0,0 @@
-
-SET mutations_sync = 2;
--- Compact parts
-CREATE TABLE test (id Int64, foo Int64 default 54321) ENGINE MergeTree ORDER BY id;
-INSERT INTO test ( id, foo ) values ( 1, 2 );
-INSERT INTO test ( id ) values ( 2 );
-SELECT '--Origin--';
-SELECT * FROM test ORDER BY id;
-ALTER TABLE test MATERIALIZE COLUMN foo;
-SELECT '--After materialize--';
-SELECT * FROM test ORDER BY id;
-DROP TABLE test;
-
--- Wide parts
-CREATE TABLE test (id Int64, foo Nullable(Int64) default 54321) ENGINE MergeTree ORDER BY id SETTINGS min_bytes_for_wide_part = 1;
-INSERT INTO test ( id, foo ) values ( 1, 2 );
-INSERT INTO test ( id ) values ( 2 );
-SELECT '--Origin--';
-SELECT * FROM test ORDER BY id;
-ALTER TABLE test MATERIALIZE COLUMN foo;
-SELECT '--After materialize--';
-SELECT * FROM test ORDER BY id;
-DROP TABLE test;
-
--- Nullable column != physically absent
-CREATE TABLE test (id Int64, foo Nullable(Int64) default 54321) ENGINE MergeTree ORDER BY id SETTINGS min_bytes_for_wide_part = 1;
-INSERT INTO test ( id, foo ) values ( 1, 2 );
-INSERT INTO test ( id, foo ) values ( 2, NULL );
-INSERT INTO test ( id ) values ( 3 );
-SELECT '--Origin--';
-SELECT * FROM test ORDER BY id;
-ALTER TABLE test MATERIALIZE COLUMN foo;
-SELECT '--After materialize--';
-SELECT * FROM test ORDER BY id;
-DROP TABLE test;
-
--- Parts with renamed column
-CREATE TABLE test (id Int64, foo Int64 default 54321) ENGINE MergeTree ORDER BY id;
-INSERT INTO test ( id, foo ) values ( 1, 2 );
-INSERT INTO test ( id ) values ( 2 );
-SELECT '--Origin--';
-SELECT * FROM test ORDER BY id;
-ALTER TABLE test RENAME COLUMN foo TO bar;
-SELECT '--After rename--';
-SELECT * FROM test ORDER BY id;
-ALTER TABLE test MATERIALIZE COLUMN bar;
-SELECT '--After materialize--';
-SELECT * FROM test ORDER BY id;
-DROP TABLE test;