fix(indexes): fail unique index creation over duplicate rows

Database::createIndex() now rethrows UniqueException instead of swallowing it with the "index already exists" DuplicateException, so a unique index over duplicate rows fails without leaving metadata behind. Memory and Redis throw UniqueException for that case, and oversized index rows map to LimitException on Postgres (54000) and MariaDB/MySQL (1071) instead of a raw PDOException.

Author: HarshMN2345

src/Database/Adapter/MariaDB.php

@@ -1893,6 +1893,11 @@ protected function processException(PDOException $e): \Exception
             return new DuplicateException('Index already exists', $e->getCode(), $e);
         }
 
+        // Index key too long
+        if ($e->getCode() === '42000' && isset($e->errorInfo[1]) && $e->errorInfo[1] === 1071) {
+            return new LimitException('Index key length exceeds the maximum', $e->getCode(), $e);
+        }
+
         // Duplicate row
         if ($e->getCode() === '23000' && isset($e->errorInfo[1]) && $e->errorInfo[1] === 1062) {
             $key = $this->getViolatedKey($e->getMessage());

src/Database/Adapter/Memory.php

@@ -1005,10 +1005,8 @@ public function createIndex(string $collection, string $id, string $type, array
         $hashTable = [];
         if ($type === Database::INDEX_UNIQUE && ! empty($attributes)) {
             // MariaDB rejects CREATE UNIQUE INDEX with errno 1062 when existing
-            // rows contain duplicates; Database::createIndex catches the resulting
-            // DuplicateException and treats it as an "orphan index" (the metadata
-            // is registered but the physical index is absent). Mirror that contract:
-            // throw DuplicateException so callers see identical end-state behavior.
+            // rows contain duplicates, which surfaces as UniqueException. Mirror
+            // that contract so Database::createIndex fails the same way.
             // Build the hash table while we scan so we can reuse it for fast
             // probes after the index lands — no second pass over the rows.
             foreach ($this->data[$key]['documents'] as $docKey => $row) {
@@ -1026,7 +1024,7 @@ public function createIndex(string $collection, string $id, string $type, array
                 }
                 $hash = \serialize($signature);
                 if (isset($hashTable[$hash])) {
-                    throw new DuplicateException('Cannot create unique index: existing rows already contain duplicate values');
+                    throw new UniqueException('Cannot create unique index: existing rows already contain duplicate values');
                 }
                 $hashTable[$hash] = $docKey;
             }

src/Database/Adapter/Postgres.php

@@ -2198,6 +2198,11 @@ protected function processException(PDOException $e): \Exception
             return new LimitException('Datetime field overflow', $e->getCode(), $e);
         }
 
+        // Index row too large
+        if ($e->getCode() === '54000' && isset($e->errorInfo[1]) && $e->errorInfo[1] === 7 && \str_contains($e->getMessage(), 'index row')) {
+            return new LimitException('Index row size exceeds the maximum', $e->getCode(), $e);
+        }
+
         // Unknown table
         if ($e->getCode() === '42P01' && isset($e->errorInfo[1]) && $e->errorInfo[1] === 7) {
             return new NotFoundException('Collection not found', $e->getCode(), $e);

src/Database/Adapter/Redis.php

@@ -2728,7 +2728,7 @@ public function createIndex(string $collection, string $id, string $type, array
                         }
                         $hash = \serialize($signature);
                         if (isset($seen[$hash])) {
-                            throw new DuplicateException('Cannot create unique index: existing rows already contain duplicate values');
+                            throw new UniqueException('Cannot create unique index: existing rows already contain duplicate values');
                         }
                         $seen[$hash] = true;
                     }

src/Database/Database.php

@@ -22,6 +22,7 @@
 use Utopia\Database\Exception\Structure as StructureException;
 use Utopia\Database\Exception\Timeout as TimeoutException;
 use Utopia\Database\Exception\Type as TypeException;
+use Utopia\Database\Exception\Unique as UniqueException;
 use Utopia\Database\Helpers\ID;
 use Utopia\Database\Helpers\Permission;
 use Utopia\Database\Helpers\Role;
@@ -4830,6 +4831,9 @@ public function createIndex(string $collection, string $id, string $type, array
                 if (!$created) {
                     throw new DatabaseException('Failed to create index');
                 }
+            } catch (UniqueException $e) {
+                // Existing rows violate the unique constraint, so no index was built.
+                throw $e;
             } catch (DuplicateException) {
                 // Metadata check (lines above) already verified index is absent
                 // from metadata. A DuplicateException from the adapter means the