Merge pull request #11057 from Potya/null_data_mods

Null data mods

src/Core/Settings.h

@@ -376,6 +376,7 @@ struct Settings : public SettingsCollection<Settings>
     M(SettingBool, materialize_ttl_after_modify, true, "Apply TTL for old data, after ALTER MODIFY TTL query", 0) \
     \
     M(SettingBool, allow_experimental_geo_types, false, "Allow geo data types such as Point, Ring, Polygon, MultiPolygon", 0) \
+    M(SettingBool, data_type_default_nullable, false, "Data types without NULL or NOT NULL will make Nullable", 0) \
     \
     /** Obsolete settings that do nothing but left for compatibility reasons. Remove each one after half a year of obsolescence. */ \
     \

src/Interpreters/InterpreterCreateQuery.cpp

@@ -7,6 +7,7 @@
 #include <Common/typeid_cast.h>
 
 #include <Core/Defines.h>
+#include <Core/Settings.h>
 
 #include <IO/WriteBufferFromFile.h>
 #include <IO/WriteHelpers.h>
@@ -71,6 +72,7 @@ namespace ErrorCodes
     extern const int BAD_DATABASE_FOR_TEMPORARY_TABLE;
     extern const int SUSPICIOUS_TYPE_FOR_LOW_CARDINALITY;
     extern const int DICTIONARY_ALREADY_EXISTS;
+    extern const int ILLEGAL_SYNTAX_FOR_DATA_TYPE;
     extern const int ILLEGAL_COLUMN;
 }
 
@@ -276,6 +278,7 @@ ColumnsDescription InterpreterCreateQuery::getColumnsDescription(
 
     /** all default_expressions as a single expression list,
      *  mixed with conversion-columns for each explicitly specified type */
+
     ASTPtr default_expr_list = std::make_shared<ASTExpressionList>();
     NamesAndTypesList column_names_and_types;
 
@@ -284,9 +287,23 @@ ColumnsDescription InterpreterCreateQuery::getColumnsDescription(
         const auto & col_decl = ast->as<ASTColumnDeclaration &>();
 
         DataTypePtr column_type = nullptr;
+
         if (col_decl.type)
         {
             column_type = DataTypeFactory::instance().get(col_decl.type);
+
+            if (col_decl.null_modifier)
+            {
+                if (column_type->isNullable())
+                    throw Exception("Cant use [NOT] NULL modifier with Nullable type", ErrorCodes::ILLEGAL_SYNTAX_FOR_DATA_TYPE);
+                if (*col_decl.null_modifier)
+                    column_type = makeNullable(column_type);
+            }
+            else if (context.getSettingsRef().data_type_default_nullable)
+            {
+                column_type = makeNullable(column_type);
+            }
+
             column_names_and_types.emplace_back(col_decl.name, column_type);
         }
         else

src/Parsers/ASTColumnDeclaration.cpp

@@ -61,6 +61,12 @@ void ASTColumnDeclaration::formatImpl(const FormatSettings & settings, FormatSta
         type->formatImpl(settings, state, frame);
     }
 
+    if (null_modifier)
+    {
+        settings.ostr << ' ' << (settings.hilite ? hilite_keyword : "")
+                      << (*null_modifier ? "" : "NOT ") << "NULL" << (settings.hilite ? hilite_none : "");
+    }
+
     if (default_expression)
     {
         settings.ostr << ' ' << (settings.hilite ? hilite_keyword : "") << default_specifier << (settings.hilite ? hilite_none : "") << ' ';

src/Parsers/ASTColumnDeclaration.h

@@ -13,6 +13,7 @@ class ASTColumnDeclaration : public IAST
 public:
     String name;
     ASTPtr type;
+    std::optional<bool> null_modifier;
     String default_specifier;
     ASTPtr default_expression;
     ASTPtr comment;

src/Parsers/ParserCreateQuery.cpp

@@ -157,7 +157,7 @@ bool ParserTablePropertyDeclaration::parseImpl(Pos & pos, ASTPtr & node, Expecte
 
     ParserIndexDeclaration index_p;
     ParserConstraintDeclaration constraint_p;
-    ParserColumnDeclaration column_p;
+    ParserColumnDeclaration column_p{true, true};
 
     ASTPtr new_node = nullptr;
 

src/Parsers/ParserCreateQuery.h

@@ -92,7 +92,8 @@ template <typename NameParser>
 class IParserColumnDeclaration : public IParserBase
 {
 public:
-    explicit IParserColumnDeclaration(bool require_type_ = true) : require_type(require_type_)
+    explicit IParserColumnDeclaration(bool require_type_ = true, bool allow_null_modifiers_ = false)
+    : require_type(require_type_), allow_null_modifiers(allow_null_modifiers_)
     {
     }
 
@@ -104,6 +105,7 @@ protected:
     bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
 
     bool require_type = true;
+    bool allow_null_modifiers = false;
 };
 
 using ParserColumnDeclaration = IParserColumnDeclaration<ParserIdentifier>;
@@ -115,6 +117,8 @@ bool IParserColumnDeclaration<NameParser>::parseImpl(Pos & pos, ASTPtr & node, E
     NameParser name_parser;
     ParserIdentifierWithOptionalParameters type_parser;
     ParserKeyword s_default{"DEFAULT"};
+    ParserKeyword s_null{"NULL"};
+    ParserKeyword s_not{"NOT"};
     ParserKeyword s_materialized{"MATERIALIZED"};
     ParserKeyword s_alias{"ALIAS"};
     ParserKeyword s_comment{"COMMENT"};
@@ -135,6 +139,7 @@ bool IParserColumnDeclaration<NameParser>::parseImpl(Pos & pos, ASTPtr & node, E
       */
     ASTPtr type;
     String default_specifier;
+    std::optional<bool> null_modifier;
     ASTPtr default_expression;
     ASTPtr comment_expression;
     ASTPtr codec_expression;
@@ -163,6 +168,17 @@ bool IParserColumnDeclaration<NameParser>::parseImpl(Pos & pos, ASTPtr & node, E
     if (require_type && !type && !default_expression)
         return false; /// reject column name without type
 
+    if (type && allow_null_modifiers)
+    {
+        if (s_not.ignore(pos, expected))
+        {
+            if (!s_null.ignore(pos, expected))
+                return false;
+            null_modifier.emplace(false);
+        }
+        else if (s_null.ignore(pos, expected))
+            null_modifier.emplace(true);
+    }
 
     if (s_comment.ignore(pos, expected))
     {
@@ -193,6 +209,8 @@ bool IParserColumnDeclaration<NameParser>::parseImpl(Pos & pos, ASTPtr & node, E
         column_declaration->children.push_back(std::move(type));
     }
 
+    column_declaration->null_modifier = null_modifier;
+
     if (default_expression)
     {
         column_declaration->default_specifier = default_specifier;

tests/queries/0_stateless/01269_create_with_null.reference

@@ -0,0 +1,4 @@
+Nullable(Int32)	Int32	Nullable(Int32)	Int32
+CREATE TABLE default.data_null\n(\n    `a` Nullable(Int32), \n    `b` Int32, \n    `c` Nullable(Int32), \n    `d` Int32\n)\nENGINE = Memory()
+Nullable(Int32)	Int32	Nullable(Int32)	Nullable(Int32)
+CREATE TABLE default.set_null\n(\n    `a` Nullable(Int32), \n    `b` Int32, \n    `c` Nullable(Int32), \n    `d` Nullable(Int32)\n)\nENGINE = Memory()

tests/queries/0_stateless/01269_create_with_null.sql

@@ -0,0 +1,50 @@
+DROP TABLE IF EXISTS data_null;
+DROP TABLE IF EXISTS set_null;
+
+SET data_type_default_nullable='false';
+
+CREATE TABLE data_null (
+    a INT NULL,
+    b INT NOT NULL,
+    c Nullable(INT),
+    d INT
+) engine=Memory();
+
+
+INSERT INTO data_null VALUES (NULL, 2, NULL, 4);
+
+SELECT toTypeName(a), toTypeName(b), toTypeName(c), toTypeName(d) FROM data_null;
+
+SHOW CREATE TABLE data_null;
+
+CREATE TABLE data_null_error (
+    a Nullable(INT) NULL,
+    b INT NOT NULL,
+    c Nullable(INT)
+) engine=Memory();  --{serverError 377}
+
+
+CREATE TABLE data_null_error (
+    a INT NULL,
+    b Nullable(INT) NOT NULL,
+    c Nullable(INT)
+) engine=Memory();  --{serverError 377}
+
+SET data_type_default_nullable='true';
+
+CREATE TABLE set_null (
+    a INT NULL,
+    b INT NOT NULL,
+    c Nullable(INT),
+    d INT
+) engine=Memory();
+
+
+INSERT INTO set_null VALUES (NULL, 2, NULL, NULL);
+
+SELECT toTypeName(a), toTypeName(b), toTypeName(c), toTypeName(d) FROM set_null;
+
+SHOW CREATE TABLE set_null;
+
+DROP TABLE data_null;
+DROP TABLE set_null;