Backport #92842 to 25.11: Fix creating type hint for path 'skip' in JSON

robot-clickhouse · robot-clickhouse · commit e383e1af6059 · 2025-12-30T13:25:23.000Z
diff --git a/src/DataTypes/DataTypeObject.cpp b/src/DataTypes/DataTypeObject.cpp
@@ -23,6 +23,7 @@
 #include <Interpreters/Context.h>
 #include <Core/Settings.h>
 #include <IO/Operators.h>
+#include <boost/algorithm/string.hpp>
 
 #include "config.h"
 
@@ -194,7 +195,11 @@ String DataTypeObject::doGetName() const
     for (const auto & path : sorted_typed_paths)
     {
         write_separator();
-        out << backQuoteIfNeed(path) << " " << typed_paths.at(path)->getName();
+        /// We must quote path "SKIP" to avoid its confusion with SKIP keyword.
+        if (boost::to_upper_copy(path) == "SKIP")
+            out << backQuote(path) << " " << typed_paths.at(path)->getName();
+        else
+            out << backQuoteIfNeed(path) << " " << typed_paths.at(path)->getName();
     }
 
     std::vector<String> sorted_skip_paths;
@@ -481,11 +486,18 @@ static DataTypePtr createObject(const ASTPtr & arguments, const DataTypeObject::
         }
         else if (object_type_argument->path_with_type)
         {
-            const auto * path_with_type = object_type_argument->path_with_type->as<ASTNameTypePair>();
+            const auto * path_with_type = object_type_argument->path_with_type->as<ASTObjectTypedPathArgument>();
             auto data_type = DataTypeFactory::instance().get(path_with_type->type);
-            if (typed_paths.contains(path_with_type->name))
-                throw Exception(ErrorCodes::BAD_ARGUMENTS, "Found duplicated path with type: {}", path_with_type->name);
-            typed_paths.emplace(path_with_type->name, data_type);
+            if (typed_paths.contains(path_with_type->path))
+                throw Exception(ErrorCodes::BAD_ARGUMENTS, "Found duplicated path with type: {}", path_with_type->path);
+
+            for (const auto & [path, _] : typed_paths)
+            {
+                if (path.starts_with(path_with_type->path + ".") || path_with_type->path.starts_with(path + "."))
+                    throw Exception(ErrorCodes::BAD_ARGUMENTS, "Found incompatible typed paths: {} and {}. One of them is a prefix of the other", path, path_with_type->path);
+            }
+
+            typed_paths.emplace(path_with_type->path, data_type);
         }
         else if (object_type_argument->skip_path)
         {
diff --git a/src/Parsers/ASTObjectTypeArgument.cpp b/src/Parsers/ASTObjectTypeArgument.cpp
@@ -1,11 +1,39 @@
 #include <IO/Operators.h>
 #include <Parsers/ASTObjectTypeArgument.h>
 #include <Parsers/CommonParsers.h>
+#include <Common/quoteString.h>
+#include <boost/algorithm/string.hpp>
 
 
 namespace DB
 {
 
+ASTPtr ASTObjectTypedPathArgument::clone() const
+{
+    auto res = std::make_shared<ASTObjectTypedPathArgument>(*this);
+    res->children.clear();
+
+    if (type)
+    {
+        res->type = type->clone();
+        res->children.push_back(res->type);
+    }
+
+    return res;
+}
+
+void ASTObjectTypedPathArgument::formatImpl(
+    WriteBuffer & ostr, const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const
+{
+    /// We must quote path "SKIP" to avoid its confusion with SKIP keyword in Object arguments.
+    if (boost::to_upper_copy(path) == "SKIP")
+        ostr << backQuote(path) << ' ';
+    else
+        ostr << backQuoteIfNeed(path) << ' ';
+
+    type->format(ostr, settings, state, frame);
+}
+
 ASTPtr ASTObjectTypeArgument::clone() const
 {
     auto res = std::make_shared<ASTObjectTypeArgument>(*this);
diff --git a/src/Parsers/ASTObjectTypeArgument.h b/src/Parsers/ASTObjectTypeArgument.h
@@ -6,6 +6,23 @@
 namespace DB
 {
 
+/// A pair of  Object path and its data type. For example: a.b.c String.
+class ASTObjectTypedPathArgument : public IAST
+{
+public:
+    /// path
+    String path;
+    /// type
+    ASTPtr type;
+
+    /** Get the text that identifies this element. */
+    String getID(char delim) const override { return "ObjectTypedPath" + (delim + path); }
+    ASTPtr clone() const override;
+
+protected:
+    void formatImpl(WriteBuffer & ostr, const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
+};
+
 /** An argument of Object data type declaration (for example for JSON). Can contain one of:
  *  - pair (path, data type)
  *  - path that should be skipped
diff --git a/src/Parsers/ParserDataType.cpp b/src/Parsers/ParserDataType.cpp
@@ -110,8 +110,8 @@ class ObjectArgumentParser : public IParserBase
         if (!type_parser.parse(pos, type, expected))
             return false;
 
-        auto name_and_type = std::make_shared<ASTNameTypePair>();
-        name_and_type->name = getIdentifierName(identifier);
+        auto name_and_type = std::make_shared<ASTObjectTypedPathArgument>();
+        name_and_type->path = getIdentifierName(identifier);
         name_and_type->type = type;
         name_and_type->children.push_back(name_and_type->type);
         argument->path_with_type = name_and_type;
diff --git a/tests/queries/0_stateless/03773_json_with_typed_path_skip.reference b/tests/queries/0_stateless/03773_json_with_typed_path_skip.reference
@@ -0,0 +1 @@
+{"skip":"Hello"}
diff --git a/tests/queries/0_stateless/03773_json_with_typed_path_skip.sql b/tests/queries/0_stateless/03773_json_with_typed_path_skip.sql
@@ -0,0 +1,2 @@
+select '{"skip" : "Hello"}'::JSON(`skip` Nullable(String));
+

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+select '{"skip" : "Hello"}'::JSON(`skip` Nullable(String));
	`2`	`+`