diff --git a/CHANGELOG.md b/CHANGELOG.md
index 00e587c..bfe834c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -63,6 +63,7 @@
 - Chg #365: Update expression namespaces according to changes in `yiisoft/db` package (@Tigrov)
 - Enh #359: Update `DMLQueryBuilder::update()` method to adapt changes in `yiisoft/db` (@rustamwin)
 - Enh #373: Adapt to `DQLQueryBuilderInterface::buildWithQueries()` signature changes in `yiisoft/db` package (@vjik)
+- Chg #378: Throw exception on "unsigned" column usage (@vjik)
 
 ## 1.3.0 March 21, 2024
 
diff --git a/src/Column/ColumnDefinitionBuilder.php b/src/Column/ColumnDefinitionBuilder.php
index cfa673f..a355bdd 100644
--- a/src/Column/ColumnDefinitionBuilder.php
+++ b/src/Column/ColumnDefinitionBuilder.php
@@ -6,6 +6,7 @@
 
 use Yiisoft\Db\Constant\ColumnType;
 use Yiisoft\Db\Constant\ReferentialAction;
+use Yiisoft\Db\Exception\NotSupportedException;
 use Yiisoft\Db\QueryBuilder\AbstractColumnDefinitionBuilder;
 use Yiisoft\Db\Schema\Column\ColumnInterface;
 
@@ -38,6 +39,10 @@ final class ColumnDefinitionBuilder extends AbstractColumnDefinitionBuilder
 
     public function build(ColumnInterface $column): string
     {
+        if ($column->isUnsigned()) {
+            throw new NotSupportedException('The "unsigned" attribute is not supported by Oracle.');
+        }
+
         return $this->buildType($column)
             . $this->buildAutoIncrement($column)
             . $this->buildDefault($column)
diff --git a/src/Column/ColumnFactory.php b/src/Column/ColumnFactory.php
index a3b4639..09d1501 100644
--- a/src/Column/ColumnFactory.php
+++ b/src/Column/ColumnFactory.php
@@ -54,6 +54,11 @@ final class ColumnFactory extends AbstractColumnFactory
     ];
     private const DATETIME_REGEX = "/^(?:TIMESTAMP|DATE|INTERVAL|to_timestamp(?:_tz)?\(|to_date\(|to_dsinterval\()\s*'(?:\d )?([^']+)/";
 
+    public function fromPseudoType(string $pseudoType, array $info = []): ColumnInterface
+    {
+        return parent::fromPseudoType($pseudoType, $info)->unsigned(false);
+    }
+
     protected function columnDefinitionParser(): ColumnDefinitionParser
     {
         return new ColumnDefinitionParser();
diff --git a/tests/Provider/ColumnFactoryProvider.php b/tests/Provider/ColumnFactoryProvider.php
index 467c5f4..efa32a2 100644
--- a/tests/Provider/ColumnFactoryProvider.php
+++ b/tests/Provider/ColumnFactoryProvider.php
@@ -18,6 +18,17 @@
 
 final class ColumnFactoryProvider extends \Yiisoft\Db\Tests\Provider\ColumnFactoryProvider
 {
+    public static function pseudoTypes(): array
+    {
+        $values = parent::pseudoTypes();
+
+        // Oracle doesn't support unsigned types
+        $values['upk'][1] = new IntegerColumn(primaryKey: true, autoIncrement: true, unsigned: false);
+        $values['ubigpk'][1] = new BigIntColumn(primaryKey: true, autoIncrement: true, unsigned: false);
+
+        return $values;
+    }
+
     public static function dbTypes(): array
     {
         return [
diff --git a/tests/Provider/QueryBuilderProvider.php b/tests/Provider/QueryBuilderProvider.php
index 856bd8d..446fbe1 100644
--- a/tests/Provider/QueryBuilderProvider.php
+++ b/tests/Provider/QueryBuilderProvider.php
@@ -287,6 +287,12 @@ public static function buildColumnDefinition(): array
 
         $values = parent::buildColumnDefinition();
 
+        // Oracle does not support unsigned types
+        unset(
+            $values['bigint(15) unsigned'],
+            $values['unsigned()'],
+        );
+
         $values[PseudoType::PK][0] = 'number(10) GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY';
         $values[PseudoType::UPK][0] = 'number(10) GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY';
         $values[PseudoType::BIGPK][0] = 'number(20) GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY';
@@ -375,7 +381,6 @@ public static function buildColumnDefinition(): array
         $values["integer()->defaultValue('')"][0] = 'number(10) DEFAULT NULL';
         $values['size(10)'][0] = 'varchar2(10)';
         $values['unique()'][0] = 'varchar2(255) UNIQUE';
-        $values['unsigned()'][0] = 'number(10)';
         $values['scale(2)'][0] = 'number(10,2)';
         $values['integer(8)->scale(2)'][0] = 'number(8)';
         $values['reference($reference)'][0] = 'number(10) REFERENCES "ref_table" ("id") ON DELETE SET NULL';