Use the same unique index name

src/Tools/SchemaTool.php

@@ -337,7 +337,14 @@ public function getSchemaFromMetadata(array $classes): Schema
 
             if (isset($class->table['uniqueConstraints'])) {
                 foreach ($class->table['uniqueConstraints'] as $indexName => $indexData) {
-                    $uniqIndex = new Index($indexName, $this->getIndexColumns($class, $indexData), true, false, [], $indexData['options'] ?? []);
+                    $uniqIndex = new Index(
+                        is_numeric($indexName) ? '' : $indexName,
+                        $this->getIndexColumns($class, $indexData),
+                        true,
+                        false,
+                        [],
+                        $indexData['options'] ?? [],
+                    );
 
                     foreach ($table->getIndexes() as $tableIndexName => $tableIndex) {
                         if ($tableIndex->isFulfilledBy($uniqIndex)) {
@@ -346,7 +353,11 @@ public function getSchemaFromMetadata(array $classes): Schema
                         }
                     }
 
-                    $table->addUniqueIndex($uniqIndex->getColumns(), is_numeric($indexName) ? null : $indexName, $indexData['options'] ?? []);
+                    $table->addUniqueIndex(
+                        $uniqIndex->getColumns(),
+                        $uniqIndex->getName() === '' ? null : $uniqIndex->getName(),
+                        $indexData['options'] ?? [],
+                    );
                 }
             }
 

tests/Tests/ORM/Functional/Ticket/DDC11246Test.php

@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\Tests\ORM\Functional\Ticket;
+
+use Doctrine\ORM\Mapping\Column;
+use Doctrine\ORM\Mapping\Entity;
+use Doctrine\ORM\Mapping\Id;
+use Doctrine\ORM\Mapping\Table;
+use Doctrine\ORM\Mapping\UniqueConstraint;
+use Doctrine\ORM\Tools\SchemaTool;
+use Doctrine\Tests\OrmFunctionalTestCase;
+use Generator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Group;
+
+#[Group('DDC-11246')]
+class DDC11246Test extends OrmFunctionalTestCase
+{
+    /** @param class-string $className */
+    #[DataProvider('classesWithoutUniqueConstraintName')]
+    public function testUniqueConstraintWithoutName(string $className): void
+    {
+        $em         = $this->getTestEntityManager();
+        $schemaTool = new SchemaTool($em);
+
+        $classes = [
+            $em->getClassMetadata($className),
+        ];
+
+        $schema = $schemaTool->getSchemaFromMetadata($classes);
+
+        self::assertTrue($schema->hasTable('unique-constraint-without-name'));
+        $table = $schema->getTable('unique-constraint-without-name');
+
+        self::assertCount(2, $table->getIndexes());
+        self::assertTrue($table->columnsAreIndexed(['name', 'phone']));
+    }
+
+    public static function classesWithoutUniqueConstraintName(): Generator
+    {
+        yield 'Entity class that passes fields for the UniqueConstraint attribute.' => [DDC11246FieldsEntity::class];
+        yield 'Entity class that passes columns for the UniqueConstraint attribute.' => [DDC11246ColumnsEntity::class];
+    }
+}
+
+#[Entity]
+#[Table('unique-constraint-without-name')]
+#[UniqueConstraint(fields: ['name', 'phone'])]
+class DDC11246FieldsEntity
+{
+    #[Id]
+    #[Column(type: 'integer')]
+    public int $id;
+
+    #[Column(type: 'string')]
+    public string $name;
+
+    #[Column(type: 'string')]
+    public string $phone;
+
+    #[Column(type: 'string')]
+    public string $email;
+}
+
+#[Entity]
+#[Table('unique-constraint-without-name')]
+#[UniqueConstraint(columns: ['name', 'phone'])]
+class DDC11246ColumnsEntity
+{
+    #[Id]
+    #[Column(type: 'integer')]
+    public int $id;
+
+    #[Column(type: 'string')]
+    public string $name;
+
+    #[Column(type: 'string')]
+    public string $phone;
+
+    #[Column(type: 'string')]
+    public string $email;
+}