Allow to specify structure hints in schema inference

docs/en/operations/settings/settings.md

@@ -3470,6 +3470,24 @@ Default value: `25'000`.
 
 The list of column names to use in schema inference for formats without column names. The format: 'column1,column2,column3,...'
 
+## schema_inference_hints {#schema_inference_hints}
+
+The list of column names and types to use as hints in schema inference for formats without schema.
+
+Example:
+
+Query:
+```sql
+desc format(JSONEachRow, '{"x" : 1, "y" : "String", "z" : "0.0.0.0" }') settings schema_inference_hints='x UInt8, z IPv4';
+```
+
+Result:
+```sql
+x	UInt8					
+y	Nullable(String)					
+z	IPv4
+```
+
 ## date_time_input_format {#date_time_input_format}
 
 Allows choosing a parser of the text representation of date and time.

src/Core/Settings.h

@@ -704,6 +704,7 @@ static constexpr UInt64 operator""_GiB(unsigned long long value)
     M(Bool, input_format_orc_skip_columns_with_unsupported_types_in_schema_inference, false, "Skip columns with unsupported types while schema inference for format ORC", 0) \
     M(Bool, input_format_arrow_skip_columns_with_unsupported_types_in_schema_inference, false, "Skip columns with unsupported types while schema inference for format Arrow", 0) \
     M(String, column_names_for_schema_inference, "", "The list of column names to use in schema inference for formats without column names. The format: 'column1,column2,column3,...'", 0) \
+    M(String, schema_inference_hints, "", "The list of column names and types to use in schema inference for formats without column names. The format: 'column1,column2,column3,...'", 0) \
     M(Bool, input_format_json_read_bools_as_numbers, true, "Allow to parse bools as numbers in JSON input formats", 0) \
     M(Bool, input_format_json_try_infer_numbers_from_strings, true, "Try to infer numbers from string fields while schema inference", 0) \
     M(Bool, input_format_try_infer_integers, true, "Try to infer numbers from string fields while schema inference in text formats", 0) \

src/Formats/FormatFactory.cpp

@@ -159,6 +159,7 @@ FormatSettings getFormatSettings(ContextPtr context, const Settings & settings)
     format_settings.msgpack.output_uuid_representation = settings.output_format_msgpack_uuid_representation;
     format_settings.max_rows_to_read_for_schema_inference = settings.input_format_max_rows_to_read_for_schema_inference;
     format_settings.column_names_for_schema_inference = settings.column_names_for_schema_inference;
+    format_settings.schema_inference_hints = settings.schema_inference_hints;
     format_settings.mysql_dump.table_name = settings.input_format_mysql_dump_table_name;
     format_settings.mysql_dump.map_column_names = settings.input_format_mysql_dump_map_column_names;
     format_settings.sql_insert.max_batch_size = settings.output_format_sql_insert_max_batch_size;
@@ -402,7 +403,10 @@ SchemaReaderPtr FormatFactory::getSchemaReader(
         throw Exception("FormatFactory: Format " + name + " doesn't support schema inference.", ErrorCodes::LOGICAL_ERROR);
 
     auto format_settings = _format_settings ? *_format_settings : getFormatSettings(context);
-    return schema_reader_creator(buf, format_settings);
+    auto schema_reader = schema_reader_creator(buf, format_settings);
+    if (schema_reader->needContext())
+        schema_reader->setContext(context);
+    return schema_reader;
 }
 
 ExternalSchemaReaderPtr FormatFactory::getExternalSchemaReader(

src/Formats/FormatSettings.h

@@ -38,6 +38,8 @@ struct FormatSettings
     UInt64 max_rows_to_read_for_schema_inference = 100;
 
     String column_names_for_schema_inference;
+    String schema_inference_hints;
+
     bool try_infer_integers = false;
     bool try_infer_dates = false;
     bool try_infer_datetimes = false;

src/Interpreters/parseColumnsListForTableFunction.cpp

@@ -44,8 +44,15 @@ bool tryParseColumnsListFromString(const std::string & structure, ColumnsDescrip
     if (!columns_list)
         return false;
 
-    columns = InterpreterCreateQuery::getColumnsDescription(*columns_list, context, false);
+    try
-    return true;
+    {
+        columns = InterpreterCreateQuery::getColumnsDescription(*columns_list, context, false);
+        return true;
+    }
+    catch (...)
+    {
+        return false;
+    }
 }
 
 }

src/Processors/Formats/ISchemaReader.cpp

@@ -2,6 +2,7 @@
 #include <Formats/ReadSchemaUtils.h>
 #include <Formats/EscapingRuleUtils.h>
 #include <DataTypes/DataTypeString.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <boost/algorithm/string.hpp>
 
 namespace DB
@@ -45,7 +46,8 @@ void chooseResultColumnType(
     {
         throw Exception(
             ErrorCodes::TYPE_MISMATCH,
-            "Automatically defined type {} for column {} in row {} differs from type defined by previous rows: {}",
+            "Automatically defined type {} for column {} in row {} differs from type defined by previous rows: {}. "
+            "You can specify the type for this column using setting schema_inference_hints",
             type->getName(),
             column_name,
             row,
@@ -60,33 +62,42 @@ void checkResultColumnTypeAndAppend(NamesAndTypesList & result, DataTypePtr & ty
         if (!default_type)
             throw Exception(
                 ErrorCodes::ONLY_NULLS_WHILE_READING_SCHEMA,
-                "Cannot determine table structure by first {} rows of data, because some columns contain only Nulls", rows_read);
+                "Cannot determine type for column {} by first {} rows of data, most likely this column contains only Nulls or empty "
+                "Arrays/Maps. You can specify the type for this column using setting schema_inference_hints",
+                name,
+                rows_read);
 
         type = default_type;
     }
     result.emplace_back(name, type);
 }
 
-IRowSchemaReader::IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_)
+IIRowSchemaReader::IIRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_)
-    : ISchemaReader(in_), format_settings(format_settings_)
+    : ISchemaReader(in_), default_type(default_type_), hints_str(format_settings_.schema_inference_hints), format_settings(format_settings_)
 {
-    if (!format_settings.column_names_for_schema_inference.empty())
+}
+
+
+void IIRowSchemaReader::setContext(ContextPtr & context)
+{
+    ColumnsDescription columns;
+    if (tryParseColumnsListFromString(hints_str, columns, context))
     {
-        /// column_names_for_schema_inference is a string in format 'column1,column2,column3,...'
+        for (const auto & [name, type] : columns.getAll())
-        boost::split(column_names, format_settings.column_names_for_schema_inference, boost::is_any_of(","));
+            hints[name] = type;
-        for (auto & column_name : column_names)
-        {
-            std::string col_name_trimmed = boost::trim_copy(column_name);
-            if (!col_name_trimmed.empty())
-                column_name = col_name_trimmed;
-        }
     }
 }
 
-IRowSchemaReader::IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_)
+IRowSchemaReader::IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_)
-    : IRowSchemaReader(in_, format_settings_)
+    : IIRowSchemaReader(in_, format_settings_)
 {
-    default_type = default_type_;
+    initColumnNames(format_settings.column_names_for_schema_inference);
+}
+
+IRowSchemaReader::IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_)
+    : IIRowSchemaReader(in_, format_settings_, default_type_)
+{
+    initColumnNames(format_settings.column_names_for_schema_inference);
 }
 
 IRowSchemaReader::IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, const DataTypes & default_types_)
@@ -104,31 +115,6 @@ NamesAndTypesList IRowSchemaReader::readSchema()
             "Most likely setting input_format_max_rows_to_read_for_schema_inference is set to 0");
 
     DataTypes data_types = readRowAndGetDataTypes();
-    for (rows_read = 1; rows_read < max_rows_to_read; ++rows_read)
-    {
-        DataTypes new_data_types = readRowAndGetDataTypes();
-        if (new_data_types.empty())
-            /// We reached eof.
-            break;
-
-        if (new_data_types.size() != data_types.size())
-            throw Exception(ErrorCodes::INCORRECT_DATA, "Rows have different amount of values");
-
-        for (size_t i = 0; i != data_types.size(); ++i)
-        {
-            /// We couldn't determine the type of this column in a new row, just skip it.
-            if (!new_data_types[i])
-                continue;
-
-            auto transform_types_if_needed = [&](DataTypePtr & type, DataTypePtr & new_type){ transformTypesIfNeeded(type, new_type, i); };
-            chooseResultColumnType(data_types[i], new_data_types[i], transform_types_if_needed, getDefaultType(i), std::to_string(i + 1), rows_read);
-        }
-    }
-
-    /// Check that we read at list one column.
-    if (data_types.empty())
-        throw Exception(ErrorCodes::EMPTY_DATA_PASSED, "Cannot read rows from the data");
-
     /// If column names weren't set, use default names 'c1', 'c2', ...
     if (column_names.empty())
     {
@@ -142,6 +128,39 @@ NamesAndTypesList IRowSchemaReader::readSchema()
             ErrorCodes::INCORRECT_DATA,
             "The number of column names {} differs with the number of types {}", column_names.size(), data_types.size());
 
+    for (size_t i = 0; i != column_names.size(); ++i)
+    {
+        auto hint_it = hints.find(column_names[i]);
+        if (hint_it != hints.end())
+            data_types[i] = hint_it->second;
+    }
+
+    for (rows_read = 1; rows_read < max_rows_to_read; ++rows_read)
+    {
+        DataTypes new_data_types = readRowAndGetDataTypes();
+        if (new_data_types.empty())
+            /// We reached eof.
+            break;
+
+        if (new_data_types.size() != data_types.size())
+            throw Exception(ErrorCodes::INCORRECT_DATA, "Rows have different amount of values");
+
+        for (size_t i = 0; i != data_types.size(); ++i)
+        {
+            /// Check if we couldn't determine the type of this column in a new row
+            /// or the type for this column was taken from hints.
+            if (!new_data_types[i] || hints.contains(column_names[i]))
+                continue;
+
+            auto transform_types_if_needed = [&](DataTypePtr & type, DataTypePtr & new_type){ transformTypesIfNeeded(type, new_type, i); };
+            chooseResultColumnType(data_types[i], new_data_types[i], transform_types_if_needed, getDefaultType(i), std::to_string(i + 1), rows_read);
+        }
+    }
+
+    /// Check that we read at list one column.
+    if (data_types.empty())
+        throw Exception(ErrorCodes::EMPTY_DATA_PASSED, "Cannot read rows from the data");
+
     NamesAndTypesList result;
     for (size_t i = 0; i != data_types.size(); ++i)
     {
@@ -152,6 +171,21 @@ NamesAndTypesList IRowSchemaReader::readSchema()
     return result;
 }
 
+void IRowSchemaReader::initColumnNames(const String & column_names_str)
+{
+    if (column_names_str.empty())
+        return;
+
+    /// column_names_for_schema_inference is a string in format 'column1,column2,column3,...'
+    boost::split(column_names, column_names_str, boost::is_any_of(","));
+    for (auto & column_name : column_names)
+    {
+        std::string col_name_trimmed = boost::trim_copy(column_name);
+        if (!col_name_trimmed.empty())
+            column_name = col_name_trimmed;
+    }
+}
+
 DataTypePtr IRowSchemaReader::getDefaultType(size_t column) const
 {
     if (default_type)
@@ -167,7 +201,7 @@ void IRowSchemaReader::transformTypesIfNeeded(DataTypePtr & type, DataTypePtr &
 }
 
 IRowWithNamesSchemaReader::IRowWithNamesSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_)
-    : ISchemaReader(in_), format_settings(format_settings_), default_type(default_type_)
+    : IIRowSchemaReader(in_, format_settings_, default_type_)
 {
 }
 
@@ -187,7 +221,11 @@ NamesAndTypesList IRowWithNamesSchemaReader::readSchema()
     names_order.reserve(names_and_types.size());
     for (const auto & [name, type] : names_and_types)
     {
-        names_to_types[name] = type;
+        auto hint_it = hints.find(name);
+        if (hint_it != hints.end())
+            names_to_types[name] = hint_it->second;
+        else
+            names_to_types[name] = type;
         names_order.push_back(name);
     }
 
@@ -205,11 +243,18 @@ NamesAndTypesList IRowWithNamesSchemaReader::readSchema()
             /// If we didn't see this column before, just add it.
             if (it == names_to_types.end())
             {
-                names_to_types[name] = new_type;
+                auto hint_it = hints.find(name);
+                if (hint_it != hints.end())
+                    names_to_types[name] = hint_it->second;
+                else
+                    names_to_types[name] = new_type;
                 names_order.push_back(name);
                 continue;
             }
 
+            if (hints.contains(name))
+                continue;
+
             auto & type = it->second;
             chooseResultColumnType(type, new_type, transform_types_if_needed, default_type, name, rows_read);
         }

src/Processors/Formats/ISchemaReader.h

@@ -37,6 +37,27 @@ protected:
 
 using CommonDataTypeChecker = std::function<DataTypePtr(const DataTypePtr &, const DataTypePtr &)>;
 
+class IIRowSchemaReader : public ISchemaReader
+{
+public:
+    IIRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_ = nullptr);
+
+    bool needContext() const override { return !hints_str.empty(); }
+    void setContext(ContextPtr & context) override;
+
+protected:
+    void setMaxRowsToRead(size_t max_rows) override { max_rows_to_read = max_rows; }
+    size_t getNumRowsRead() const override { return rows_read; }
+
+    size_t max_rows_to_read;
+    size_t rows_read = 0;
+    CommonDataTypeChecker common_type_checker;
+    DataTypePtr default_type;
+    String hints_str;
+    FormatSettings format_settings;
+    std::unordered_map<String, DataTypePtr> hints;
+};
+
 /// Base class for schema inference for formats that read data row by row.
 /// It reads data row by row (up to max_rows_to_read), determines types of columns
 /// for each row and compare them with types from the previous rows. If some column
@@ -44,12 +65,12 @@ using CommonDataTypeChecker = std::function<DataTypePtr(const DataTypePtr &, con
 /// (from argument default_type_) will be used for this column or the exception
 /// will be thrown (if default type is not set). If different columns have different
 /// default types, you can provide them by default_types_ argument.
-class IRowSchemaReader : public ISchemaReader
+class IRowSchemaReader : public IIRowSchemaReader
 {
 public:
-    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings);
+    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_);
-    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings, DataTypePtr default_type_);
+    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_);
-    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings, const DataTypes & default_types_);
+    IRowSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, const DataTypes & default_types_);
 
     NamesAndTypesList readSchema() override;
 
@@ -62,19 +83,12 @@ protected:
 
     void setColumnNames(const std::vector<String> & names) { column_names = names; }
 
-    void setMaxRowsToRead(size_t max_rows) override { max_rows_to_read = max_rows; }
+    virtual void transformTypesIfNeeded(DataTypePtr & type, DataTypePtr & new_type, size_t index);
-    size_t getNumRowsRead() const override { return rows_read; }
-
-    FormatSettings format_settings;
-
-    virtual void transformTypesIfNeeded(DataTypePtr & type, DataTypePtr & new_type, size_t column_idx);
 
 private:
-
     DataTypePtr getDefaultType(size_t column) const;
-    size_t max_rows_to_read;
+    void initColumnNames(const String & column_names_str);
-    size_t rows_read = 0;
+
-    DataTypePtr default_type;
     DataTypes default_types;
     std::vector<String> column_names;
 };
@@ -84,7 +98,7 @@ private:
 /// Differ from IRowSchemaReader in that after reading a row we get
 /// a map {column_name : type} and some columns may be missed in a single row
 /// (in this case we will use types from the previous rows for missed columns).
-class IRowWithNamesSchemaReader : public ISchemaReader
+class IRowWithNamesSchemaReader : public IIRowSchemaReader
 {
 public:
     IRowWithNamesSchemaReader(ReadBuffer & in_, const FormatSettings & format_settings_, DataTypePtr default_type_ = nullptr);
@@ -98,17 +112,7 @@ protected:
     /// Set eof = true if can't read more data.
     virtual NamesAndTypesList readRowAndGetNamesAndDataTypes(bool & eof) = 0;
 
-    void setMaxRowsToRead(size_t max_rows) override { max_rows_to_read = max_rows; }
-    size_t getNumRowsRead() const override { return rows_read; }
-
     virtual void transformTypesIfNeeded(DataTypePtr & type, DataTypePtr & new_type);
-
-    FormatSettings format_settings;
-
-private:
-    size_t max_rows_to_read;
-    size_t rows_read = 0;
-    DataTypePtr default_type;
 };
 
 /// Base class for schema inference for formats that don't need any data to

src/Processors/Formats/Impl/JSONEachRowRowInputFormat.h

@@ -88,7 +88,7 @@ private:
 class JSONEachRowSchemaReader : public IRowWithNamesSchemaReader
 {
 public:
-    JSONEachRowSchemaReader(ReadBuffer & in_, bool json_strings, const FormatSettings & format_settings);
+    JSONEachRowSchemaReader(ReadBuffer & in_, bool json_strings, const FormatSettings & format_settings_);
 
 private:
     NamesAndTypesList readRowAndGetNamesAndDataTypes(bool & eof) override;

src/TableFunctions/Hive/TableFunctionHive.cpp

@@ -14,7 +14,7 @@
 #include <Storages/Hive/StorageHive.h>
 #include <Storages/checkAndGetLiteralArgument.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Common/logger_useful.h>
 
 namespace DB

src/TableFunctions/ITableFunctionFileLike.cpp

@@ -1,5 +1,5 @@
 #include <TableFunctions/ITableFunctionFileLike.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTLiteral.h>

src/TableFunctions/TableFunctionExecutable.cpp

@@ -2,7 +2,7 @@
 
 #include <Common/Exception.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTSelectWithUnionQuery.h>

src/TableFunctions/TableFunctionFile.cpp

@@ -1,5 +1,5 @@
 #include <TableFunctions/TableFunctionFile.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 
 #include "Parsers/IAST_fwd.h"
 #include "registerTableFunctions.h"

src/TableFunctions/TableFunctionGenerateRandom.cpp

@@ -12,7 +12,7 @@
 #include <TableFunctions/ITableFunction.h>
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionGenerateRandom.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 
 #include "registerTableFunctions.h"
 

src/TableFunctions/TableFunctionHDFS.cpp

@@ -6,7 +6,7 @@
 #include <Storages/ColumnsDescription.h>
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionHDFS.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 
 namespace DB
 {

src/TableFunctions/TableFunctionHDFSCluster.cpp

@@ -13,7 +13,7 @@
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionHDFS.h>
 #include <TableFunctions/TableFunctionHDFSCluster.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Parsers/ASTLiteral.h>
 #include <Parsers/IAST_fwd.h>
 

src/TableFunctions/TableFunctionInput.cpp

@@ -1,6 +1,6 @@
 #include <TableFunctions/TableFunctionInput.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTLiteral.h>
 #include <Common/Exception.h>

src/TableFunctions/TableFunctionMongoDB.cpp

@@ -9,7 +9,7 @@
 
 #include <TableFunctions/TableFunctionMongoDB.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <TableFunctions/registerTableFunctions.h>
 #include <Storages/checkAndGetLiteralArgument.h>
 #include <Storages/ColumnsDescription.h>

src/TableFunctions/TableFunctionNull.cpp

@@ -3,7 +3,7 @@
 #include <Parsers/ASTFunction.h>
 #include <Storages/checkAndGetLiteralArgument.h>
 #include <Storages/StorageNull.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionNull.h>
 #include <Interpreters/evaluateConstantExpression.h>

src/TableFunctions/TableFunctionS3.cpp

@@ -7,7 +7,7 @@
 #include <Interpreters/Context.h>
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionS3.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Parsers/ASTLiteral.h>
 #include <Storages/checkAndGetLiteralArgument.h>
 #include <Storages/StorageS3.h>

src/TableFunctions/TableFunctionS3Cluster.cpp

@@ -14,7 +14,7 @@
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionS3.h>
 #include <TableFunctions/TableFunctionS3Cluster.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Parsers/ASTLiteral.h>
 #include <Parsers/ASTExpressionList.h>
 #include <Parsers/IAST_fwd.h>

src/TableFunctions/TableFunctionURL.cpp

@@ -9,7 +9,7 @@
 #include <Storages/StorageURL.h>
 #include <Storages/StorageExternalDistributed.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Formats/FormatFactory.h>
 
 

src/TableFunctions/TableFunctionValues.cpp

@@ -11,7 +11,7 @@
 
 #include <TableFunctions/TableFunctionValues.h>
 #include <TableFunctions/TableFunctionFactory.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 
 #include <Interpreters/convertFieldToType.h>
 #include <Interpreters/evaluateConstantExpression.h>

src/TableFunctions/TableFunctionViewIfPermitted.cpp

@@ -8,7 +8,7 @@
 #include <TableFunctions/ITableFunction.h>
 #include <TableFunctions/TableFunctionFactory.h>
 #include <TableFunctions/TableFunctionViewIfPermitted.h>
-#include <TableFunctions/parseColumnsListForTableFunction.h>
+#include <Interpreters/parseColumnsListForTableFunction.h>
 #include <Interpreters/evaluateConstantExpression.h>
 #include "registerTableFunctions.h"
 

tests/queries/0_stateless/02383_schema_inference_hints.reference

@@ -0,0 +1,16 @@
+x	UInt8					
+y	Nullable(String)					
+z	IPv4					
+x	UInt8					
+y	Nullable(String)					
+z	IPv4					
+x	Nullable(UInt32)					
+x	Array(UInt32)					
+x	Map(String, String)					
+c1	UInt8					
+c2	Nullable(String)					
+c3	IPv4					
+x	UInt8					
+y	Nullable(String)					
+z	IPv4					
+x	Nullable(UInt32)					

tests/queries/0_stateless/02383_schema_inference_hints.sql

@@ -0,0 +1,10 @@
+-- Tags: no-fasttest
+desc format(JSONEachRow, '{"x" : 1, "y" : "String", "z" : "0.0.0.0" }') settings schema_inference_hints='x UInt8, z IPv4';
+desc format(JSONEachRow, '{"x" : 1, "y" : "String"}\n{"z" : "0.0.0.0", "y" : "String2"}\n{"x" : 2}') settings schema_inference_hints='x UInt8, z IPv4';
+desc format(JSONEachRow, '{"x" : null}') settings schema_inference_hints='x Nullable(UInt32)';
+desc format(JSONEachRow, '{"x" : []}') settings schema_inference_hints='x Array(UInt32)';
+desc format(JSONEachRow, '{"x" : {}}') settings schema_inference_hints='x Map(String, String)';
+
+desc format(CSV, '1,"String","0.0.0.0"') settings schema_inference_hints='c1 UInt8, c3 IPv4';
+desc format(CSV, '1,"String","0.0.0.0"') settings schema_inference_hints='x UInt8, z IPv4', column_names_for_schema_inference='x, y, z';
+desc format(CSV, '\\N') settings schema_inference_hints='x Nullable(UInt32)', column_names_for_schema_inference='x';