From cc7fa551fe2aafe2ca055c409f40498e62a70653 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Wed, 11 Mar 2026 12:14:42 +0300
Subject: [PATCH] orm: postgresql backend: invalid syntax for inserting default
 values (fixes #18319)

---
 vlib/db/pg/orm.v         |  4 ++--
 vlib/db/pg/pg_orm_test.v | 30 ++++++++++++++++++++++++++++++
 vlib/orm/orm.v           |  2 +-
 vlib/orm/orm_fn_test.v   | 16 ++++++++++++++++
 4 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/vlib/db/pg/orm.v b/vlib/db/pg/orm.v
index 104f13316..5f580cb5f 100644
--- a/vlib/db/pg/orm.v
+++ b/vlib/db/pg/orm.v
@@ -30,8 +30,8 @@ pub fn (db DB) select(config orm.SelectConfig, data orm.QueryData, where orm.Que
 
 // insert is used internally by V's ORM for processing `INSERT ` queries
 pub fn (db DB) insert(table orm.Table, data orm.QueryData) ! {
-	query, converted_data := orm.orm_stmt_gen(.default, table, '"', .insert, true, '$',
-		1, data, orm.QueryData{})
+	query, converted_data := orm.orm_stmt_gen(.pg, table, '"', .insert, true, '$', 1,
+		data, orm.QueryData{})
 	pg_stmt_worker(db, query, converted_data, orm.QueryData{})!
 }
 
diff --git a/vlib/db/pg/pg_orm_test.v b/vlib/db/pg/pg_orm_test.v
index 179df7019..10677415c 100644
--- a/vlib/db/pg/pg_orm_test.v
+++ b/vlib/db/pg/pg_orm_test.v
@@ -36,6 +36,11 @@ struct TestDefaultAttribute {
 	created_at string @[default: 'CURRENT_TIMESTAMP'; sql_type: 'TIMESTAMP']
 }
 
+struct TestInsertDefaultValues {
+	id      int    @[primary; sql: serial]
+	example string @[default: '']
+}
+
 @[comment: 'This is a table comment']
 struct TestCommentAttribute {
 	id         string @[primary; sql: serial]
@@ -244,6 +249,31 @@ fn test_pg_orm() {
 	}!
 	assert ['gen_random_uuid()', '', 'CURRENT_TIMESTAMP'] == information_schema_defaults_results
 
+	/** test inserting only default values
+	*/
+	sql db {
+		create table TestInsertDefaultValues
+	}!
+
+	model_default_values := TestInsertDefaultValues{
+		example: ''
+	}
+
+	sql db {
+		insert model_default_values into TestInsertDefaultValues
+	}!
+
+	inserted_default_values := sql db {
+		select from TestInsertDefaultValues
+	}!
+
+	sql db {
+		drop table TestInsertDefaultValues
+	}!
+
+	assert inserted_default_values.len == 1
+	assert inserted_default_values[0].example == ''
+
 	/** test comment attribute
 	*/
 	sql db {
diff --git a/vlib/orm/orm.v b/vlib/orm/orm.v
index aa7bbcfdb..aad38c957 100644
--- a/vlib/orm/orm.v
+++ b/vlib/orm/orm.v
@@ -616,7 +616,7 @@ pub fn orm_stmt_gen(sql_dialect SQLDialect, table Table, q string, kind StmtKind
 
 			are_values_empty := values.len == 0
 
-			if sql_dialect == .sqlite && are_values_empty {
+			if sql_dialect in [.sqlite, .pg] && are_values_empty {
 				str += 'DEFAULT VALUES'
 			} else {
 				str += '('
diff --git a/vlib/orm/orm_fn_test.v b/vlib/orm/orm_fn_test.v
index 36021b5a8..f2b06fb8b 100644
--- a/vlib/orm/orm_fn_test.v
+++ b/vlib/orm/orm_fn_test.v
@@ -47,6 +47,22 @@ fn test_orm_stmt_gen_insert() {
 	assert query == "INSERT INTO 'Test' ('test', 'a') VALUES (?0, ?1);"
 }
 
+fn test_orm_stmt_gen_insert_default_values_pg() {
+	table := orm.Table{
+		name: 'Test'
+	}
+	query, converted := orm.orm_stmt_gen(.pg, table, "'", .insert, true, '$', 1, orm.QueryData{
+		fields:      ['id', 'example']
+		data:        [orm.Primitive(0), orm.Primitive('')]
+		types:       []
+		kinds:       []
+		auto_fields: [0, 1]
+	}, orm.QueryData{})
+	assert query == "INSERT INTO 'Test' DEFAULT VALUES;"
+	assert converted.fields.len == 0
+	assert converted.data.len == 0
+}
+
 fn test_orm_stmt_gen_delete() {
 	table := orm.Table{
 		name: 'Test'
-- 
2.39.5