Add default policy to ColumnMeta

ydb/core/tx/schemeshard/ut_export/ut_export.cpp

@@ -281,8 +281,42 @@ Y_UNIT_TEST_SUITE(TExportToS3Tests) {
 
         const TVector<TString> tables = {R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
-            Columns { Name: "value" Type: "Utf8" }
+            Columns {
+                Name: "key"
+                Type: "Utf8"
+                DefaultFromLiteral {
+                    type {
+                        optional_type {
+                            item {
+                                type_id: UTF8
+                            }
+                        }
+                    }
+                    value {
+                        items {
+                            text_value: "b"
+                        }
+                    }
+                }
+            }
+            Columns {
+                Name: "value"
+                Type: "Utf8"
+                DefaultFromLiteral {
+                    type {
+                        optional_type {
+                            item {
+                                type_id: UTF8
+                            }
+                        }
+                    }
+                    value {
+                        items {
+                            text_value: "a"
+                        }
+                    }
+                }
+            }
             KeyColumnNames: ["key"]
             PartitionConfig {
               ColumnFamilies {
@@ -331,6 +365,20 @@ Y_UNIT_TEST_SUITE(TExportToS3Tests) {
     }
   }
   not_null: false
+  from_literal {
+    type {
+      optional_type {
+        item {
+          type_id: UTF8
+        }
+      }
+    }
+    value {
+      items {
+        text_value: "b"
+      }
+    }
+  }
 }
 columns {
   name: "value"
@@ -342,6 +390,20 @@ columns {
     }
   }
   not_null: false
+  from_literal {
+    type {
+      optional_type {
+        item {
+          type_id: UTF8
+        }
+      }
+    }
+    value {
+      items {
+        text_value: "a"
+      }
+    }
+  }
 }
 primary_key: "key"
 storage_settings {

ydb/core/ydb_convert/table_description.cpp

@@ -151,11 +151,11 @@ bool BuildAlterTableAddIndexRequest(const Ydb::Table::AlterTableRequest* req, NK
     if (flags & NKqpProto::TKqpSchemeOperation::FLAG_PG_MODE) {
         settings->set_pg_mode(true);
     }
-    
+
     if (flags & NKqpProto::TKqpSchemeOperation::FLAG_IF_NOT_EXISTS) {
         settings->set_if_not_exist(true);
     }
-    
+
     settings->set_source_path(req->path());
     auto tableIndex = settings->mutable_index();
     tableIndex->CopyFrom(req->add_indexes(0));
@@ -390,6 +390,59 @@ static Ydb::Type* AddColumn(Ydb::Table::ColumnMeta* newColumn, const TColumn& co
         }
     }
     newColumn->set_not_null(column.GetNotNull());
+    return columnType;
+}
+
+template <>
+Ydb::Type* AddColumn<NKikimrSchemeOp::TColumnDescription>(Ydb::Table::ColumnMeta* newColumn, const NKikimrSchemeOp::TColumnDescription& column) {
+    newColumn->set_name(column.GetName());
+
+    Ydb::Type* columnType = nullptr;
+    auto* typeDesc = NPg::TypeDescFromPgTypeName(column.GetType());
+    if (typeDesc) {
+        columnType = newColumn->mutable_type();
+        auto* pg = columnType->mutable_pg_type();
+        pg->set_type_name(NPg::PgTypeNameFromTypeDesc(typeDesc));
+        pg->set_type_modifier(NPg::TypeModFromPgTypeName(column.GetType()));
+        pg->set_oid(NPg::PgTypeIdFromTypeDesc(typeDesc));
+        pg->set_typlen(0);
+        pg->set_typmod(0);
+    } else {
+        NYql::NProto::TypeIds protoType;
+        if (!NYql::NProto::TypeIds_Parse(column.GetType(), &protoType)) {
+            throw NYql::TErrorException(NKikimrIssues::TIssuesIds::DEFAULT_ERROR)
+                << "Got invalid type: " << column.GetType() << " for column: " << column.GetName();
+        }
+
+        if (column.GetNotNull()) {
+            columnType = newColumn->mutable_type();
+        } else {
+            columnType = newColumn->mutable_type()->mutable_optional_type()->mutable_item();
+        }
+        Y_ENSURE(columnType);
+        if (protoType == NYql::NProto::TypeIds::Decimal) {
+            auto typeParams = columnType->mutable_decimal_type();
+            // TODO: Change TEvDescribeSchemeResult to return decimal params
+            typeParams->set_precision(22);
+            typeParams->set_scale(9);
+        } else {
+            NMiniKQL::ExportPrimitiveTypeToProto(protoType, *columnType);
+        }
+    }
+    newColumn->set_not_null(column.GetNotNull());
+    switch (column.GetDefaultValueCase()) {
+        case NKikimrSchemeOp::TColumnDescription::kDefaultFromSequence: {
+            auto from_sequence = newColumn->mutable_from_sequence();
+            from_sequence->set_path(column.GetDefaultFromSequence());
+            break;
+        }
+        case NKikimrSchemeOp::TColumnDescription::kDefaultFromLiteral: {
+            auto from_literal = newColumn->mutable_from_literal();
+            *from_literal = column.GetDefaultFromLiteral();
+            break;
+        }
+        default: break;
+    }
 
     return columnType;
 }

ydb/public/api/protos/ydb_table.proto

@@ -333,6 +333,10 @@ message TableProfile {
     CachingPolicy caching_policy = 7;
 }
 
+message SequenceDescription {
+    string path = 1;
+}
+
 message ColumnMeta {
     // Name of column
     string name = 1;
@@ -342,6 +346,11 @@ message ColumnMeta {
     string family = 3;
     // Column nullability
     optional bool not_null = 4;
+    // Default value policy
+    oneof default_policy {
+        SequenceDescription from_sequence = 5;
+        TypedValue from_literal = 6;
+    }
 }
 
 message DateTypeColumnModeSettings {