Skip materialized view checking if source table does not exist

src/Core/Settings.h

@@ -467,6 +467,7 @@ class IColumn;
     M(Int64, max_partitions_to_read, -1, "Limit the max number of partitions that can be accessed in one query. <= 0 means unlimited.", 0) \
     M(Bool, check_query_single_value_result, true, "Return check query result as single 1/0 value", 0) \
     M(Bool, allow_drop_detached, false, "Allow ALTER TABLE ... DROP DETACHED PART[ITION] ... queries", 0) \
+    M(Bool, skip_materialized_view_checking_if_source_table_not_exist, false, "Allow attaching to a materialized view even if dependent tables are inaccessible.", 0) \
     \
     M(UInt64, postgresql_connection_pool_size, 16, "Connection pool size for PostgreSQL table engine and database engine.", 0) \
     M(UInt64, postgresql_connection_pool_wait_timeout, 5000, "Connection pool push/pop timeout on empty pool for PostgreSQL table engine and database engine. By default it will block on empty pool.", 0) \

src/Interpreters/InterpreterCreateQuery.cpp

@@ -97,6 +97,7 @@ namespace ErrorCodes
     extern const int ILLEGAL_COLUMN;
     extern const int LOGICAL_ERROR;
     extern const int UNKNOWN_DATABASE;
+    extern const int UNKNOWN_TABLE;
     extern const int PATH_ACCESS_DENIED;
     extern const int NOT_IMPLEMENTED;
     extern const int ENGINE_REQUIRED;
@@ -1076,6 +1077,62 @@ void InterpreterCreateQuery::assertOrSetUUID(ASTCreateQuery & create, const Data
     }
 }
 
+void InterpreterCreateQuery::checkTypecompatibleForMaterializeView(const ASTCreateQuery & create)
+{
+    if (StoragePtr to_table = DatabaseCatalog::instance().tryGetTable(
+            {create.to_table_id.database_name, create.to_table_id.table_name, create.to_table_id.uuid},
+            getContext()
+        ))
+        {
+            Block input_block;
+            try
+            {
+                if (getContext()->getSettingsRef().allow_experimental_analyzer)
+                {
+                    input_block = InterpreterSelectQueryAnalyzer::getSampleBlock(create.select->clone(), getContext());
+                }
+                else
+                {
+                    input_block = InterpreterSelectWithUnionQuery(create.select->clone(),
+                        getContext(),
+                        SelectQueryOptions().analyze()).getSampleBlock();
+                }
+            }
+            catch (const Exception & e)
+            {
+                if (getContext()->getSettingsRef().skip_materialized_view_checking_if_source_table_not_exist &&
+                    e.code() == ErrorCodes::UNKNOWN_TABLE && create.attach
+                )
+                {
+                    LOG_WARNING(&Poco::Logger::get("InterpreterSelectQuery"), "{}", e.message());
+                    return;
+                }
+                else
+                {
+                    throw;
+                }
+            }
+
+            Block output_block = to_table->getInMemoryMetadataPtr()->getSampleBlock();
+
+            ColumnsWithTypeAndName input_columns;
+            ColumnsWithTypeAndName output_columns;
+            for (const auto & input_column : input_block)
+            {
+                if (const auto * output_column = output_block.findByName(input_column.name))
+                {
+                    input_columns.push_back(input_column.cloneEmpty());
+                    output_columns.push_back(output_column->cloneEmpty());
+                }
+            }
+
+            ActionsDAG::makeConvertingActions(
+                input_columns,
+                output_columns,
+                ActionsDAG::MatchColumnsMode::Position
+            );
+        }
+}
 
 BlockIO InterpreterCreateQuery::createTable(ASTCreateQuery & create)
 {
@@ -1203,43 +1260,7 @@ BlockIO InterpreterCreateQuery::createTable(ASTCreateQuery & create)
     /// Check type compatible for materialized dest table and select columns
     if (create.select && create.is_materialized_view && create.to_table_id)
     {
-        if (StoragePtr to_table = DatabaseCatalog::instance().tryGetTable(
-            {create.to_table_id.database_name, create.to_table_id.table_name, create.to_table_id.uuid},
-            getContext()
-        ))
-        {
-            Block input_block;
-
-            if (getContext()->getSettingsRef().allow_experimental_analyzer)
-            {
-                input_block = InterpreterSelectQueryAnalyzer::getSampleBlock(create.select->clone(), getContext());
-            }
-            else
-            {
-                input_block = InterpreterSelectWithUnionQuery(create.select->clone(),
-                    getContext(),
-                    SelectQueryOptions().analyze()).getSampleBlock();
-            }
-
-            Block output_block = to_table->getInMemoryMetadataPtr()->getSampleBlock();
-
-            ColumnsWithTypeAndName input_columns;
-            ColumnsWithTypeAndName output_columns;
-            for (const auto & input_column : input_block)
-            {
-                if (const auto * output_column = output_block.findByName(input_column.name))
-                {
-                    input_columns.push_back(input_column.cloneEmpty());
-                    output_columns.push_back(output_column->cloneEmpty());
-                }
-            }
-
-            ActionsDAG::makeConvertingActions(
-                input_columns,
-                output_columns,
-                ActionsDAG::MatchColumnsMode::Position
-            );
-        }
+        checkTypecompatibleForMaterializeView(create);
     }
 
     DatabasePtr database;

src/Interpreters/InterpreterCreateQuery.h

@@ -95,6 +95,8 @@ class InterpreterCreateQuery : public IInterpreter, WithMutableContext
     BlockIO doCreateOrReplaceTable(ASTCreateQuery & create, const InterpreterCreateQuery::TableProperties & properties);
     /// Inserts data in created table if it's CREATE ... SELECT
     BlockIO fillTableIfNeeded(const ASTCreateQuery & create);
+    /// Check type compatible for materialized dest table and select columns
+    void checkTypecompatibleForMaterializeView(const ASTCreateQuery & create);
 
     void assertOrSetUUID(ASTCreateQuery & create, const DatabasePtr & database) const;
 

tests/queries/0_stateless/02696_ignore_inacc_tables_mat_view_atttach.reference

@@ -0,0 +1,2 @@
+3	some_val
+3	9

tests/queries/0_stateless/02696_ignore_inacc_tables_mat_view_atttach.sql

@@ -0,0 +1,29 @@
+SET send_logs_level = 'fatal';
+
+CREATE TABLE test_table (n Int32, s String) ENGINE MergeTree PARTITION BY n ORDER BY n;
+
+CREATE TABLE mview_backend (n Int32, n2 Int64) ENGINE MergeTree PARTITION BY n ORDER BY n;
+
+CREATE MATERIALIZED VIEW mview TO mview_backend AS SELECT n, n * n AS "n2" FROM test_table;
+
+DROP TABLE test_table;
+
+DETACH TABLE mview;
+
+/* Check that we get an exception with the option. */
+
+SET skip_materialized_view_checking_if_source_table_not_exist = 0;
+ATTACH TABLE mview; --{serverError 60}
+
+/* Check that we don't get an exception with the option. */
+SET skip_materialized_view_checking_if_source_table_not_exist = 1;
+ATTACH TABLE mview;
+
+/* Check if the data in the materialized view is updated after the restore.*/
+CREATE TABLE test_table (n Int32, s String) ENGINE MergeTree PARTITION BY n ORDER BY n;
+
+INSERT INTO test_table VALUES (3,'some_val');
+
+SELECT n,s  FROM test_table ORDER BY n;
+SELECT n,n2 FROM mview ORDER by n;
+