Merge pull request #36345 from ucasfl/throw-no-data

Add setting throw_if_no_data_to_insert

src/Client/ClientBase.cpp

@@ -1058,7 +1058,13 @@ void ClientBase::processInsertQuery(const String & query_to_execute, ASTPtr pars
     /// Process the query that requires transferring data blocks to the server.
     const auto parsed_insert_query = parsed_query->as<ASTInsertQuery &>();
     if ((!parsed_insert_query.data && !parsed_insert_query.infile) && (is_interactive || (!stdin_is_a_tty && std_in.eof())))
-        throw Exception("No data to insert", ErrorCodes::NO_DATA_TO_INSERT);
+    {
+        const auto & settings = global_context->getSettingsRef();
+        if (settings.throw_if_no_data_to_insert)
+            throw Exception("No data to insert", ErrorCodes::NO_DATA_TO_INSERT);
+        else
+            return;
+    }
 
     connection->sendQuery(
         connection_parameters.timeouts,

src/Core/Settings.h

@@ -582,6 +582,7 @@ class IColumn;
     M(Bool, allow_experimental_object_type, false, "Allow Object and JSON data types", 0) \
     M(String, insert_deduplication_token, "", "If not empty, used for duplicate detection instead of data digest", 0) \
     M(Bool, throw_on_unsupported_query_inside_transaction, true, "Throw exception if unsupported query is used inside transaction", 0) \
+    M(Bool, throw_if_no_data_to_insert, true, "Enables or disables empty INSERTs, disable by default", 0) \
 // End of COMMON_SETTINGS
 // Please add settings related to formats into the FORMAT_FACTORY_SETTINGS and move obsolete settings to OBSOLETE_SETTINGS.
 

src/Parsers/ParserInsertQuery.cpp

@@ -41,6 +41,7 @@ bool ParserInsertQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
     ParserKeyword s_with("WITH");
     ParserToken s_lparen(TokenType::OpeningRoundBracket);
     ParserToken s_rparen(TokenType::ClosingRoundBracket);
+    ParserToken s_semicolon(TokenType::Semicolon);
     ParserIdentifier name_p(true);
     ParserList columns_p(std::make_unique<ParserInsertElement>(), std::make_unique<ParserToken>(TokenType::Comma), false);
     ParserFunction table_function_p{false};
@@ -146,8 +147,10 @@ bool ParserInsertQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
     /// After FROM INFILE we expect FORMAT, SELECT, WITH or nothing.
     if (!infile && s_values.ignore(pos, expected))
     {
-        /// If VALUES is defined in query, everything except setting will be parsed as data
-        data = pos->begin;
+        /// If VALUES is defined in query, everything except setting will be parsed as data,
+        /// and if values followed by semicolon, the data should be null.
+        if (!s_semicolon.checkWithoutMoving(pos, expected))
+            data = pos->begin;
         format_str = "Values";
     }
     else if (s_format.ignore(pos, expected))

src/Server/GRPCServer.cpp

@@ -956,7 +956,13 @@ namespace
             if (!insert_query)
                 throw Exception("Query requires data to insert, but it is not an INSERT query", ErrorCodes::NO_DATA_TO_INSERT);
             else
-                throw Exception("No data to insert", ErrorCodes::NO_DATA_TO_INSERT);
+            {
+                const auto & settings = query_context->getSettingsRef();
+                if (settings.throw_if_no_data_to_insert)
+                    throw Exception("No data to insert", ErrorCodes::NO_DATA_TO_INSERT);
+                else
+                    return;
+            }
         }
 
         /// This is significant, because parallel parsing may be used.

tests/queries/0_stateless/02267_insert_empty_data.sql

@@ -0,0 +1,11 @@
+DROP TABLE IF EXISTS t;
+
+CREATE TABLE t (n UInt32) ENGINE=Memory;
+
+INSERT INTO t VALUES; -- { clientError 108 }
+
+set throw_if_no_data_to_insert = 0;
+
+INSERT INTO t VALUES;
+
+DROP TABLE t;