fix: resolve schema-qualified table names in getFieldData() and protectIdentifiers()

system/Database/BaseConnection.php

@@ -1338,7 +1338,7 @@ public function protectIdentifiers($item, bool $prefixSingle = false, ?bool $pro
 
     private function protectDotItem(string $item, string $alias, bool $protectIdentifiers, bool $fieldExists): string
     {
-        $parts = explode('.', $item);
+        $parts = array_map(fn (string $part): string => trim($part, $this->escapeChar), explode('.', $item));
 
         // Does the first segment of the exploded item match
         // one of the aliases previously identified? If so,

system/Database/Postgre/Connection.php

@@ -325,11 +325,20 @@ protected function _listColumns($table = ''): string
      */
     protected function _fieldData(string $table): array
     {
+        $parts  = explode('.', $table);
+        $table  = array_pop($parts);
+        $schema = array_pop($parts);
+
         $sql = 'SELECT "column_name", "data_type", "character_maximum_length", "numeric_precision", "column_default",  "is_nullable"
             FROM "information_schema"."columns"
             WHERE LOWER("table_name") = '
-                . $this->escape(strtolower($table))
-                . ' ORDER BY "ordinal_position"';
+                . $this->escape(strtolower($table));
+
+        if ($schema !== null) {
+            $sql .= ' AND LOWER("table_schema") = ' . $this->escape(strtolower($schema));
+        }
+
+        $sql .= ' ORDER BY "ordinal_position"';
 
         if (($query = $this->query($sql)) === false) {
             throw new DatabaseException(lang('Database.failGetFieldData'));

system/Database/SQLSRV/Connection.php

@@ -314,12 +314,20 @@ protected function _enableForeignKeyChecks()
      */
     protected function _fieldData(string $table): array
     {
+        $parts  = explode('.', $table);
+        $table  = array_pop($parts);
+        $schema = array_pop($parts);
+
         $sql = 'SELECT
                 COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION,
                 COLUMN_DEFAULT, IS_NULLABLE
             FROM INFORMATION_SCHEMA.COLUMNS
             WHERE TABLE_NAME= ' . $this->escape(($table));
 
+        if ($schema !== null) {
+            $sql .= ' AND TABLE_SCHEMA = ' . $this->escape($schema);
+        }
+
         if (($query = $this->query($sql)) === false) {
             throw new DatabaseException(lang('Database.failGetFieldData'));
         }

system/Database/SQLite3/Connection.php

@@ -270,7 +270,12 @@ public function getFieldNames($tableName)
      */
     protected function _fieldData(string $table): array
     {
-        if (false === $query = $this->query('PRAGMA TABLE_INFO(' . $this->protectIdentifiers($table, true, null, false) . ')')) {
+        $parts  = explode('.', $table);
+        $table  = array_pop($parts);
+        $schema = array_pop($parts);
+        $pragma = ($schema === null ? '' : $this->escapeIdentifiers($schema) . '.') . 'TABLE_INFO(' . $this->protectIdentifiers($table, true, null, false) . ')';
+
+        if (false === $query = $this->query('PRAGMA ' . $pragma)) {
             throw new DatabaseException(lang('Database.failGetFieldData'));
         }
 

tests/system/Database/BaseConnectionTest.php

@@ -372,6 +372,11 @@ public static function provideProtectIdentifiers(): iterable
             'quoted table alias'        => [false, true, false, '"jobs" "j"', '"jobs" "j"'],
             'quoted table alias prefix' => [true, true, false, '"jobs" "j"', '"test_jobs" "j"'],
 
+            'schema.table'                   => [false, true, false, 'tenant.jobs', '"tenant"."test_jobs"'],
+            'schema.table prefix'            => [true, true, false, 'tenant.jobs', '"tenant"."test_jobs"'],
+            'quoted schema.table prefix'     => [true, true, false, '"tenant"."test_jobs"', '"tenant"."test_jobs"'],
+            'quoted schema.table no-protect' => [true, false, false, '"tenant"."test_jobs"', 'tenant.test_jobs'],
+
             'table.*'             => [false, true, true, 'jobs.*', '"test_jobs".*'], // Prefixed because it has segments
             'table.* prefix'      => [true, true, true, 'jobs.*', '"test_jobs".*'],
             'table.column'        => [false, true, true, 'users.id', '"test_users"."id"'], // Prefixed because it has segments

tests/system/Database/Live/AbstractGetFieldDataTestCase.php

@@ -57,6 +57,30 @@ protected function tearDown(): void
         $this->forge->dropTable($this->table, true);
     }
 
+    protected function qualifiedTableName(): string
+    {
+        return match ($this->db->DBDriver) {
+            'MySQLi'  => $this->db->getDatabase() . '.' . $this->table,
+            'OCI8'    => $this->db->username . '.' . $this->table,
+            'Postgre' => 'public.' . $this->table,
+            'SQLite3' => 'main.' . $this->table,
+            'SQLSRV'  => 'dbo.' . $this->table,
+            default   => $this->markTestSkipped('No qualified table name is defined for ' . $this->db->DBDriver . '.'),
+        };
+    }
+
+    public function testGetFieldDataWithQualifiedTableName(): void
+    {
+        $this->createTableForDefault();
+
+        $toArray = static fn (stdClass $field): array => (array) $field;
+
+        $this->assertSame(
+            array_map($toArray, $this->db->getFieldData($this->table)),
+            array_map($toArray, $this->db->getFieldData($this->qualifiedTableName())),
+        );
+    }
+
     protected function createTableForDefault(): void
     {
         $this->forge->dropTable($this->table, true);

user_guide_src/source/changelogs/v4.7.5.rst

@@ -54,6 +54,7 @@ Bugs Fixed
 - **Cookie:** Fixed a bug where ``Cookie`` instances allowed invalid characters in path, domain, and prefix attributes rejected by ``setcookie()`` and ``setrawcookie()``.
 - **Database:** Fixed a bug where rebuilding a SQLite3 table (e.g., ``Forge::dropColumn()``, ``Forge::modifyColumn()``, ``Forge::dropForeignKey()`` and ``Forge::dropPrimaryKey()``) corrupted the table names referenced by its foreign keys when ``DBPrefix`` was set.
 - **Database:** Fixed a bug where Postgre query failures were silently ignored when ``DBDebug`` was enabled and PHP warnings were disabled. A ``DatabaseException`` is now thrown.
+- **Database:** Fixed a bug where ``getFieldData()`` failed for a schema-qualified table name on Postgre, SQLSRV and SQLite3, and where ``protectIdentifiers()`` prefixed an already protected segment of a dotted identifier a second time.
 - **Debug:** Fixed a bug where ``Timer::start()`` treated ``0.0`` as an empty value and substituted the current time.
 - **Files:** Fixed a bug where ``File::move()`` and ``UploadedFile::move()`` set executable and overly permissive file permissions (``0777 & ~umask()`` instead of ``0666 & ~umask()``), and ``UploadedFile::move()`` targeted the parent directory instead of the destination file for ``chmod()``.
 - **Helpers:** Fixed a bug where ``get_dir_file_info()`` returned incomplete entries for subdirectories and missing files instead of omitting them.