allow to ignore CREATE INDEX query for better SQL syntax compatibility

src/Core/Settings.h

@@ -774,6 +774,7 @@ class IColumn;
     M(Bool, keeper_map_strict_mode, false, "Enforce additional checks during operations on KeeperMap. E.g. throw an exception on an insert for already existing key", 0) \
     M(UInt64, extract_kvp_max_pairs_per_row, 1000, "Max number pairs that can be produced by extractKeyValuePairs function. Used to safeguard against consuming too much memory.", 0) \
     M(Timezone, session_timezone, "", "The default timezone for current session or query. The server default timezone if empty.", 0) \
+    M(Bool, allow_create_index_without_type, false, "Allow CREATE INDEX query without TYPE. Query will be ignored. Made for SQL compatibility tests.", 0)\
     // End of COMMON_SETTINGS
     // Please add settings related to formats into the FORMAT_FACTORY_SETTINGS and move obsolete settings to OBSOLETE_SETTINGS.
 

src/Interpreters/InterpreterCreateIndexQuery.cpp

@@ -15,6 +15,8 @@ namespace DB
 namespace ErrorCodes
 {
     extern const int TABLE_IS_READ_ONLY;
+    extern const int LOGICAL_ERROR;
+    extern const int INCORRECT_QUERY;
 }
 
 
@@ -23,6 +25,21 @@ BlockIO InterpreterCreateIndexQuery::execute()
     auto current_context = getContext();
     const auto & create_index = query_ptr->as<ASTCreateIndexQuery &>();
 
+    // Noop if allow_create_index_without_type = true. throw otherwise
+    if (!create_index.index_decl->as<ASTIndexDeclaration>()->type)
+    {
+        if (!current_context->getSettingsRef().allow_create_index_without_type)
+        {
+            throw Exception(ErrorCodes::INCORRECT_QUERY, "CREATE INDEX without TYPE is forbidden."
+                " SET allow_create_index_without_type=1 to ignore this statements.");
+        }
+        else
+        {
+            // Nothing to do
+            return {};
+        }
+    }
+
     AccessRightsElements required_access;
     required_access.emplace_back(AccessType::ALTER_ADD_INDEX, create_index.getDatabase(), create_index.getTable());
 

src/Parsers/ASTIndexDeclaration.cpp

@@ -13,8 +13,8 @@ ASTPtr ASTIndexDeclaration::clone() const
     auto res = std::make_shared<ASTIndexDeclaration>();
 
     res->name = name;
+    if (granularity)
         res->granularity = granularity;
-
     if (expr)
         res->set(res->expr, expr->clone());
     if (type)
@@ -25,6 +25,8 @@ ASTPtr ASTIndexDeclaration::clone() const
 
 void ASTIndexDeclaration::formatImpl(const FormatSettings & s, FormatState & state, FormatStateStacked frame) const
 {
+    if (expr)
+    {
         if (part_of_create_index_query)
         {
             s.ostr << "(";
@@ -37,11 +39,18 @@ void ASTIndexDeclaration::formatImpl(const FormatSettings & s, FormatState & sta
             s.ostr << " ";
             expr->formatImpl(s, state, frame);
         }
+    }
 
+    if (type)
+    {
         s.ostr << (s.hilite ? hilite_keyword : "") << " TYPE " << (s.hilite ? hilite_none : "");
         type->formatImpl(s, state, frame);
+    }
+    if (granularity)
+    {
         s.ostr << (s.hilite ? hilite_keyword : "") << " GRANULARITY " << (s.hilite ? hilite_none : "");
         s.ostr << granularity;
+    }
 }
 
 }

src/Parsers/ParserCreateIndexQuery.cpp

@@ -17,24 +17,36 @@ bool ParserCreateIndexDeclaration::parseImpl(Pos & pos, ASTPtr & node, Expected
 {
     ParserKeyword s_type("TYPE");
     ParserKeyword s_granularity("GRANULARITY");
-
+    ParserToken open(TokenType::OpeningRoundBracket);
+    ParserToken close(TokenType::ClosingRoundBracket);
+    ParserOrderByExpressionList order_list;
     ParserDataType data_type_p;
     ParserExpression expression_p;
     ParserUnsignedInteger granularity_p;
 
     ASTPtr expr;
+    ASTPtr order;
     ASTPtr type;
     ASTPtr granularity;
 
+    if (open.ignore(pos, expected))
+    {
+        if (!order_list.parse(pos, order, expected))
+            return false;
+
+        if (!close.ignore(pos, expected))
+            return false;
+    }
     /// Skip name parser for SQL-standard CREATE INDEX
-    if (!expression_p.parse(pos, expr, expected))
+    else if (!expression_p.parse(pos, expr, expected))
         return false;
 
-    if (!s_type.ignore(pos, expected))
-        return false;
 
+    if (s_type.ignore(pos, expected))
+    {
         if (!data_type_p.parse(pos, type, expected))
             return false;
+    }
 
     if (s_granularity.ignore(pos, expected))
     {
@@ -45,13 +57,14 @@ bool ParserCreateIndexDeclaration::parseImpl(Pos & pos, ASTPtr & node, Expected
     auto index = std::make_shared<ASTIndexDeclaration>();
     index->part_of_create_index_query = true;
     index->set(index->expr, expr);
+    if (type)
         index->set(index->type, type);
 
     if (granularity)
         index->granularity = granularity->as<ASTLiteral &>().value.safeGet<UInt64>();
     else
     {
-        if (index->type->name == "annoy")
+        if (index->type && index->type->name == "annoy")
             index->granularity = ASTIndexDeclaration::DEFAULT_ANNOY_INDEX_GRANULARITY;
         else
             index->granularity = ASTIndexDeclaration::DEFAULT_INDEX_GRANULARITY;