diff --git a/ext/pdo/tests/pdo_011.phpt b/ext/pdo/tests/pdo_011.phpt
deleted file mode 100644
index 88c2677c08991..0000000000000
--- a/ext/pdo/tests/pdo_011.phpt
+++ /dev/null
@@ -1,305 +0,0 @@
---TEST--
-PDO Common: PDO::FETCH_FUNC and statement overloading
---EXTENSIONS--
-pdo
---SKIPIF--
-<?php
-$dir = getenv('REDIR_TEST_DIR');
-if (false == $dir) die('skip no driver');
-require_once $dir . 'pdo_test.inc';
-PDOTest::skip();
-?>
---FILE--
-<?php
-if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
-require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
-$db = PDOTest::factory();
-
-$db->exec('CREATE TABLE test011(id int NOT NULL PRIMARY KEY, val VARCHAR(10), grp VARCHAR(10))');
-$db->exec("INSERT INTO test011 VALUES(1, 'A', 'Group1')");
-$db->exec("INSERT INTO test011 VALUES(2, 'B', 'Group1')");
-$db->exec("INSERT INTO test011 VALUES(3, 'C', 'Group2')");
-$db->exec("INSERT INTO test011 VALUES(4, 'D', 'Group2')");
-
-class DerivedStatement extends PDOStatement
-{
-    private function __construct(public $name, $db)
-    {
-        echo __METHOD__ . "($name)\n";
-    }
-
-    function reTrieve($id, $val) {
-        echo __METHOD__ . "($id,$val)\n";
-        return array($id=>$val);
-    }
-}
-
-$select1 = $db->prepare('SELECT grp, id FROM test011');
-$select2 = $db->prepare('SELECT id, val FROM test011');
-$derived = $db->prepare('SELECT id, val FROM test011', array(PDO::ATTR_STATEMENT_CLASS=>array('DerivedStatement', array('Overloaded', $db))));
-
-class Test1
-{
-    public function __construct(public $id, public $val)
-    {
-        echo __METHOD__ . "($id,$val)\n";
-    }
-
-    static public function factory($id, $val)
-    {
-        echo __METHOD__ . "($id,$val)\n";
-        return new self($id, $val);
-    }
-}
-
-function callback($id,$val='N/A')
-{
-    echo __METHOD__ . "($id,$val)\n";
-    return array($id=>$val);
-}
-
-$f = new Test1(0,0);
-
-$select1->execute();
-var_dump($select1->fetchAll(PDO::FETCH_FUNC|PDO::FETCH_GROUP, 'callback'));
-
-$select2->execute();
-var_dump($select2->fetchAll(PDO::FETCH_FUNC, 'callback'));
-
-$select2->execute();
-var_dump($select2->fetchAll(PDO::FETCH_FUNC, array('Test1','factory')));
-
-$select2->execute();
-var_dump($select2->fetchAll(PDO::FETCH_FUNC, array($f, 'factory')));
-
-var_dump(get_class($derived));
-$derived->execute();
-var_dump($derived->fetchAll(PDO::FETCH_FUNC, array($derived, 'retrieve')));
-$derived->execute();
-var_dump($derived->fetchAll(PDO::FETCH_FUNC, array($derived, 'reTrieve')));
-$derived->execute();
-var_dump($derived->fetchAll(PDO::FETCH_FUNC, array($derived, 'RETRIEVE')));
-
-?>
---CLEAN--
-<?php
-require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
-$db = PDOTest::factory();
-PDOTest::dropTableIfExists($db, "test011");
-?>
---EXPECTF--
-DerivedStatement::__construct(Overloaded)
-Test1::__construct(0,0)
-callback(1,N/A)
-callback(2,N/A)
-callback(3,N/A)
-callback(4,N/A)
-array(2) {
-  ["Group1"]=>
-  array(2) {
-    [0]=>
-    array(1) {
-      [1]=>
-      string(3) "N/A"
-    }
-    [1]=>
-    array(1) {
-      [2]=>
-      string(3) "N/A"
-    }
-  }
-  ["Group2"]=>
-  array(2) {
-    [0]=>
-    array(1) {
-      [3]=>
-      string(3) "N/A"
-    }
-    [1]=>
-    array(1) {
-      [4]=>
-      string(3) "N/A"
-    }
-  }
-}
-callback(1,A)
-callback(2,B)
-callback(3,C)
-callback(4,D)
-array(4) {
-  [0]=>
-  array(1) {
-    [1]=>
-    string(1) "A"
-  }
-  [1]=>
-  array(1) {
-    [2]=>
-    string(1) "B"
-  }
-  [2]=>
-  array(1) {
-    [3]=>
-    string(1) "C"
-  }
-  [3]=>
-  array(1) {
-    [4]=>
-    string(1) "D"
-  }
-}
-Test1::factory(1,A)
-Test1::__construct(1,A)
-Test1::factory(2,B)
-Test1::__construct(2,B)
-Test1::factory(3,C)
-Test1::__construct(3,C)
-Test1::factory(4,D)
-Test1::__construct(4,D)
-array(4) {
-  [0]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "1"
-    ["val"]=>
-    string(1) "A"
-  }
-  [1]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "2"
-    ["val"]=>
-    string(1) "B"
-  }
-  [2]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "3"
-    ["val"]=>
-    string(1) "C"
-  }
-  [3]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "4"
-    ["val"]=>
-    string(1) "D"
-  }
-}
-Test1::factory(1,A)
-Test1::__construct(1,A)
-Test1::factory(2,B)
-Test1::__construct(2,B)
-Test1::factory(3,C)
-Test1::__construct(3,C)
-Test1::factory(4,D)
-Test1::__construct(4,D)
-array(4) {
-  [0]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "1"
-    ["val"]=>
-    string(1) "A"
-  }
-  [1]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "2"
-    ["val"]=>
-    string(1) "B"
-  }
-  [2]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "3"
-    ["val"]=>
-    string(1) "C"
-  }
-  [3]=>
-  object(Test1)#%d (2) {
-    ["id"]=>
-    string(1) "4"
-    ["val"]=>
-    string(1) "D"
-  }
-}
-string(16) "DerivedStatement"
-DerivedStatement::reTrieve(1,A)
-DerivedStatement::reTrieve(2,B)
-DerivedStatement::reTrieve(3,C)
-DerivedStatement::reTrieve(4,D)
-array(4) {
-  [0]=>
-  array(1) {
-    [1]=>
-    string(1) "A"
-  }
-  [1]=>
-  array(1) {
-    [2]=>
-    string(1) "B"
-  }
-  [2]=>
-  array(1) {
-    [3]=>
-    string(1) "C"
-  }
-  [3]=>
-  array(1) {
-    [4]=>
-    string(1) "D"
-  }
-}
-DerivedStatement::reTrieve(1,A)
-DerivedStatement::reTrieve(2,B)
-DerivedStatement::reTrieve(3,C)
-DerivedStatement::reTrieve(4,D)
-array(4) {
-  [0]=>
-  array(1) {
-    [1]=>
-    string(1) "A"
-  }
-  [1]=>
-  array(1) {
-    [2]=>
-    string(1) "B"
-  }
-  [2]=>
-  array(1) {
-    [3]=>
-    string(1) "C"
-  }
-  [3]=>
-  array(1) {
-    [4]=>
-    string(1) "D"
-  }
-}
-DerivedStatement::reTrieve(1,A)
-DerivedStatement::reTrieve(2,B)
-DerivedStatement::reTrieve(3,C)
-DerivedStatement::reTrieve(4,D)
-array(4) {
-  [0]=>
-  array(1) {
-    [1]=>
-    string(1) "A"
-  }
-  [1]=>
-  array(1) {
-    [2]=>
-    string(1) "B"
-  }
-  [2]=>
-  array(1) {
-    [3]=>
-    string(1) "C"
-  }
-  [3]=>
-  array(1) {
-    [4]=>
-    string(1) "D"
-  }
-}
diff --git a/ext/pdo/tests/pdo_fetch_func_001.phpt b/ext/pdo/tests/pdo_fetch_func_001.phpt
new file mode 100644
index 0000000000000..93af976d38c6f
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_func_001.phpt
@@ -0,0 +1,114 @@
+--TEST--
+PDO Common: Testing PDO::FETCH_FUNC with various callables
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_001(id int NOT NULL PRIMARY KEY, pl_name VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_001 VALUES (1, 'php')");
+$db->exec("INSERT INTO pdo_fetch_function_001 VALUES (2, 'sql')");
+
+echo "Anonymous function:\n";
+$st = $db->query('SELECT * FROM pdo_fetch_function_001');
+$st->fetchAll(
+    PDO::FETCH_FUNC,
+    function($x, $y) {
+        echo $x, ' ', $y, PHP_EOL;
+    }
+);
+
+echo "Internal function:\n";
+$st = $db->query('SELECT pl_name FROM pdo_fetch_function_001');
+var_dump($st->fetchAll(PDO::FETCH_FUNC, 'strtoupper'));
+
+echo "Relative class callable:\n";
+class foo {
+    public function method($x) {
+        return __METHOD__ . "($x)";
+    }
+}
+class bar extends foo {
+    public function __construct($db) {
+        $st = $db->query('SELECT * FROM pdo_fetch_function_001');
+        var_dump($st->fetchAll(PDO::FETCH_FUNC, [$this, 'parent::method']));
+    }
+
+    static public function factory($x, $y) {
+        return __METHOD__ . "($x, $y)";
+    }
+}
+
+$bar = new bar($db);
+
+echo '["bar", "factory"] callable:', "\n";
+$st = $db->query('SELECT * FROM pdo_fetch_function_001');
+var_dump($st->fetchAll(PDO::FETCH_FUNC, ['bar', 'factory']));
+
+echo '[$bar, "factory"] callable:', "\n";
+$st = $db->query('SELECT * FROM pdo_fetch_function_001');
+var_dump($st->fetchAll(PDO::FETCH_FUNC, [$bar, 'factory']));
+
+echo '"bar::factory" callable:', "\n";
+$st = $db->query('SELECT * FROM pdo_fetch_function_001');
+var_dump($st->fetchAll(PDO::FETCH_FUNC, 'bar::factory'));
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_001");
+?>
+--EXPECTF--
+Anonymous function:
+1 php
+2 sql
+Internal function:
+array(2) {
+  [0]=>
+  string(3) "PHP"
+  [1]=>
+  string(3) "SQL"
+}
+Relative class callable:
+
+Deprecated: Callables of the form ["bar", "parent::method"] are deprecated in %s on line %d
+array(2) {
+  [0]=>
+  string(14) "foo::method(1)"
+  [1]=>
+  string(14) "foo::method(2)"
+}
+["bar", "factory"] callable:
+array(2) {
+  [0]=>
+  string(20) "bar::factory(1, php)"
+  [1]=>
+  string(20) "bar::factory(2, sql)"
+}
+[$bar, "factory"] callable:
+array(2) {
+  [0]=>
+  string(20) "bar::factory(1, php)"
+  [1]=>
+  string(20) "bar::factory(2, sql)"
+}
+"bar::factory" callable:
+array(2) {
+  [0]=>
+  string(20) "bar::factory(1, php)"
+  [1]=>
+  string(20) "bar::factory(2, sql)"
+}
diff --git a/ext/pdo/tests/pdo_fetch_function_basic.phpt b/ext/pdo/tests/pdo_fetch_function_basic.phpt
new file mode 100644
index 0000000000000..522eca7005a06
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_basic.phpt
@@ -0,0 +1,99 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with a simple callback
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_basic(id int NOT NULL PRIMARY KEY, val1 VARCHAR(10), val2 VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_basic VALUES (1, 'A', 'alpha')");
+$db->exec("INSERT INTO pdo_fetch_function_basic VALUES (2, 'B', 'beta')");
+$db->exec("INSERT INTO pdo_fetch_function_basic VALUES (3, 'C', 'gamma')");
+$db->exec("INSERT INTO pdo_fetch_function_basic VALUES (4, 'D', 'delta')");
+
+echo "SELECT id, val1:\n";
+
+function associateValWithId(int $id, string $val): array {
+    echo __FUNCTION__, '(', var_export($id, true), ', ', var_export($val, true) , ")\n";
+    return [$id=>$val];
+}
+
+$selectIdVal = $db->prepare('SELECT id, val1 FROM pdo_fetch_function_basic');
+$selectIdVal->execute();
+$result = $selectIdVal->fetchAll(PDO::FETCH_FUNC, 'associateValWithId');
+var_dump($result);
+
+echo "SELECT *:\n";
+
+function selectAllCallback(int $id, string $val1, string $val2): string {
+    echo __FUNCTION__, '(', var_export($id, true),
+        ', ', var_export($val1, true),
+        ', ', var_export($val2, true) , ")\n";
+    return $val1 . $val2;
+}
+
+$selectAll = $db->prepare('SELECT * FROM pdo_fetch_function_basic');
+$selectAll->execute();
+$result = $selectAll->fetchAll(PDO::FETCH_FUNC, 'selectAllCallback');
+var_dump($result);
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_basic");
+?>
+--EXPECT--
+SELECT id, val1:
+associateValWithId(1, 'A')
+associateValWithId(2, 'B')
+associateValWithId(3, 'C')
+associateValWithId(4, 'D')
+array(4) {
+  [0]=>
+  array(1) {
+    [1]=>
+    string(1) "A"
+  }
+  [1]=>
+  array(1) {
+    [2]=>
+    string(1) "B"
+  }
+  [2]=>
+  array(1) {
+    [3]=>
+    string(1) "C"
+  }
+  [3]=>
+  array(1) {
+    [4]=>
+    string(1) "D"
+  }
+}
+SELECT *:
+selectAllCallback(1, 'A', 'alpha')
+selectAllCallback(2, 'B', 'beta')
+selectAllCallback(3, 'C', 'gamma')
+selectAllCallback(4, 'D', 'delta')
+array(4) {
+  [0]=>
+  string(6) "Aalpha"
+  [1]=>
+  string(5) "Bbeta"
+  [2]=>
+  string(6) "Cgamma"
+  [3]=>
+  string(6) "Ddelta"
+}
diff --git a/ext/pdo/tests/pdo_fetch_function_incorrect_call.phpt b/ext/pdo/tests/pdo_fetch_function_incorrect_call.phpt
new file mode 100644
index 0000000000000..63c342b598f73
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_incorrect_call.phpt
@@ -0,0 +1,50 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with a call that is invalid
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_incorrect_call(id int NOT NULL PRIMARY KEY, val1 VARCHAR(10), val2 VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_call VALUES(1, 'A', 'alpha')");
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_call VALUES(2, 'B', 'beta')");
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_call VALUES(3, 'C', 'gamma')");
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_call VALUES(4, 'D', 'delta')");
+
+$selectIdVal = $db->prepare('SELECT val1, val2 FROM pdo_fetch_function_incorrect_call');
+
+function bogusCallback(stdClass $obj, string $str, array $arr) {
+    echo "Called\n";
+    return "how?";
+}
+
+$selectIdVal->execute();
+
+echo "Fetch all with bogus call:\n";
+try {
+    $result = $selectIdVal->fetchAll(PDO::FETCH_FUNC, 'bogusCallback');
+    var_dump($result);
+} catch (Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), PHP_EOL;
+}
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_incorrect_call");
+?>
+--EXPECT--
+Fetch all with bogus call:
+TypeError: bogusCallback(): Argument #1 ($obj) must be of type stdClass, string given
diff --git a/ext/pdo/tests/pdo_fetch_function_incorrect_callables.phpt b/ext/pdo/tests/pdo_fetch_function_incorrect_callables.phpt
new file mode 100644
index 0000000000000..f06ae3c6a6b6f
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_incorrect_callables.phpt
@@ -0,0 +1,96 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with invalid callables
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_incorrect_callable(id int NOT NULL PRIMARY KEY, pl_name VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_callable VALUES (1, 'php')");
+$db->exec("INSERT INTO pdo_fetch_function_incorrect_callable VALUES (2, 'sql')");
+$stmt = $db->query('SELECT * FROM pdo_fetch_function_incorrect_callable');
+
+class Bar {
+    static private function privateStatic($x, $y) {
+        return $x;
+    }
+
+    public function instanceMethod($x, $y) {
+        return $x .'==='. $y;
+    }
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, 'nothing'));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, ''));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, NULL));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, 1));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, ['self', 'foo']));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, ['bar', 'instanceMethod']));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, ['bar', 'privateStatic']));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+try {
+    var_dump($stmt->fetchAll(PDO::FETCH_FUNC, ['bar', 'nonexistent']));
+} catch (\Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), \PHP_EOL;
+}
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_incorrect_callable");
+?>
+--EXPECT--
+TypeError: function "nothing" not found or invalid function name
+TypeError: function "" not found or invalid function name
+TypeError: PDOStatement::fetchAll(): Argument #2 must be a callable, null given
+TypeError: no array or string given
+TypeError: cannot access "self" when no class scope is active
+TypeError: non-static method Bar::instanceMethod() cannot be called statically
+TypeError: cannot access private method Bar::privateStatic()
+TypeError: class Bar does not have a method "nonexistent"
diff --git a/ext/pdo/tests/pdo_fetch_function_overload_statement_class.phpt b/ext/pdo/tests/pdo_fetch_function_overload_statement_class.phpt
new file mode 100644
index 0000000000000..d9c1a01eeeaa3
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_overload_statement_class.phpt
@@ -0,0 +1,65 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC and statement overloading
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_overload_statement_class(id int NOT NULL PRIMARY KEY, val VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_overload_statement_class VALUES (1, 'A')");
+$db->exec("INSERT INTO pdo_fetch_function_overload_statement_class VALUES (2, 'B')");
+$db->exec("INSERT INTO pdo_fetch_function_overload_statement_class VALUES (3, 'C')");
+$db->exec("INSERT INTO pdo_fetch_function_overload_statement_class VALUES (4, 'D')");
+
+class DerivedStatement extends PDOStatement
+{
+    private function __construct(public $name, $db)
+    {
+        echo __METHOD__ . "($name)\n";
+    }
+
+    function reTrieve($id, $val) {
+        echo __METHOD__ . "($id,$val)\n";
+        return "$id => $val";
+    }
+}
+
+$derived = $db->prepare('SELECT id, val FROM pdo_fetch_function_overload_statement_class', [PDO::ATTR_STATEMENT_CLASS => ['DerivedStatement', ['Overloaded', $db]]]);
+var_dump(get_class($derived));
+$derived->execute();
+var_dump($derived->fetchAll(PDO::FETCH_FUNC, [$derived, 'retrieve']));
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_overload_statement_class");
+?>
+--EXPECT--
+DerivedStatement::__construct(Overloaded)
+string(16) "DerivedStatement"
+DerivedStatement::reTrieve(1,A)
+DerivedStatement::reTrieve(2,B)
+DerivedStatement::reTrieve(3,C)
+DerivedStatement::reTrieve(4,D)
+array(4) {
+  [0]=>
+  string(6) "1 => A"
+  [1]=>
+  string(6) "2 => B"
+  [2]=>
+  string(6) "3 => C"
+  [3]=>
+  string(6) "4 => D"
+}
diff --git a/ext/pdo/tests/pdo_fetch_function_with_grouping.phpt b/ext/pdo/tests/pdo_fetch_function_with_grouping.phpt
new file mode 100644
index 0000000000000..e3d20347c8130
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_with_grouping.phpt
@@ -0,0 +1,63 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with a simple callback and grouping (PDO::FETCH_FUNC|PDO::FETCH_GROUP)
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_with_grouping(id int NOT NULL PRIMARY KEY, val VARCHAR(10), grp VARCHAR(10))');
+
+$db->exec("INSERT INTO pdo_fetch_function_with_grouping VALUES (1, 'A', 'Group1')");
+$db->exec("INSERT INTO pdo_fetch_function_with_grouping VALUES (2, 'B', 'Group1')");
+$db->exec("INSERT INTO pdo_fetch_function_with_grouping VALUES (3, 'C', 'Group2')");
+$db->exec("INSERT INTO pdo_fetch_function_with_grouping VALUES (4, 'D', 'Group2')");
+
+$selectGroupId = $db->prepare('SELECT grp, id, val FROM pdo_fetch_function_with_grouping');
+
+function associateValWithId(int $id, string $value) {
+    echo __FUNCTION__, '(', var_export($id, true), ', ', var_export($value, true) , ")\n";
+    return "$id => $value";
+}
+
+$selectGroupId->execute();
+$result = $selectGroupId->fetchAll(PDO::FETCH_FUNC|PDO::FETCH_GROUP, 'associateValWithId');
+var_dump($result);
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_with_grouping");
+?>
+--EXPECT--
+associateValWithId(1, 'A')
+associateValWithId(2, 'B')
+associateValWithId(3, 'C')
+associateValWithId(4, 'D')
+array(2) {
+  ["Group1"]=>
+  array(2) {
+    [0]=>
+    string(6) "1 => A"
+    [1]=>
+    string(6) "2 => B"
+  }
+  ["Group2"]=>
+  array(2) {
+    [0]=>
+    string(6) "3 => C"
+    [1]=>
+    string(6) "4 => D"
+  }
+}
diff --git a/ext/pdo/tests/pdo_fetch_function_with_unique.phpt b/ext/pdo/tests/pdo_fetch_function_with_unique.phpt
new file mode 100644
index 0000000000000..5dc412242030c
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_with_unique.phpt
@@ -0,0 +1,55 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with a simple callback and uniqueness (PDO::FETCH_FUNC|PDO::FETCH_UNIQUE)
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_with_uniqueness(id int NOT NULL PRIMARY KEY, val1 VARCHAR(10), val2 VARCHAR(10))');
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness VALUES (1, 'A', 'alpha')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness VALUES (2, 'B', 'beta')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness VALUES (3, 'C', 'gamma')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness VALUES (4, 'D', 'delta')");
+
+function to_upper_with_log(string $str): string {
+    echo __FUNCTION__, '(', var_export($str, true), ')', PHP_EOL;
+    return strtoupper($str);
+}
+
+$pdoQuery = $db->prepare('SELECT val1, val2 FROM pdo_fetch_function_with_uniqueness');
+$pdoQuery->execute();
+$result = $pdoQuery->fetchAll(PDO::FETCH_FUNC|PDO::FETCH_UNIQUE, 'to_upper_with_log');
+var_dump($result);
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_with_uniqueness");
+?>
+--EXPECT--
+to_upper_with_log('alpha')
+to_upper_with_log('beta')
+to_upper_with_log('gamma')
+to_upper_with_log('delta')
+array(4) {
+  ["A"]=>
+  string(5) "ALPHA"
+  ["B"]=>
+  string(4) "BETA"
+  ["C"]=>
+  string(5) "GAMMA"
+  ["D"]=>
+  string(5) "DELTA"
+}
diff --git a/ext/pdo/tests/pdo_fetch_function_with_unique_and_grouping.phpt b/ext/pdo/tests/pdo_fetch_function_with_unique_and_grouping.phpt
new file mode 100644
index 0000000000000..5a9b15ed17137
--- /dev/null
+++ b/ext/pdo/tests/pdo_fetch_function_with_unique_and_grouping.phpt
@@ -0,0 +1,52 @@
+--TEST--
+PDO Common: PDO::FETCH_FUNC with a simple callback and uniqueness+grouping (PDO::FETCH_FUNC|PDO::FETCH_UNIQUE|PDO::FETCH_GROUP)
+--EXTENSIONS--
+pdo
+--SKIPIF--
+<?php
+$dir = getenv('REDIR_TEST_DIR');
+if (false == $dir) die('skip no driver');
+require_once $dir . 'pdo_test.inc';
+PDOTest::skip();
+?>
+--FILE--
+<?php
+if (getenv('REDIR_TEST_DIR') === false) putenv('REDIR_TEST_DIR='.__DIR__ . '/../../pdo/tests/');
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+
+$db->exec('CREATE TABLE pdo_fetch_function_with_uniqueness_and_grouping(id int NOT NULL PRIMARY KEY, val1 VARCHAR(10), val2 VARCHAR(10), grp VARCHAR(10))');
+// Firebird does not allow inserting multiple rows with INSERT INTO
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness_and_grouping VALUES (1, 'A', 'alpha', 'Group1')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness_and_grouping VALUES (2, 'B', 'beta', 'Group1')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness_and_grouping VALUES (3, 'C', 'gamma', 'Group2')");
+$db->exec("INSERT INTO pdo_fetch_function_with_uniqueness_and_grouping VALUES (4, 'D', 'delta', 'Group2')");
+
+function to_upper_with_log(string $str): string {
+    echo __FUNCTION__, '(', var_export($str, true), ')', PHP_EOL;
+    return strtoupper($str);
+}
+
+$pdoQuery = $db->prepare('SELECT grp, val2, val1 FROM pdo_fetch_function_with_uniqueness_and_grouping');
+$pdoQuery->execute();
+$result = $pdoQuery->fetchAll(PDO::FETCH_FUNC|PDO::FETCH_UNIQUE|PDO::FETCH_GROUP, 'to_upper_with_log');
+var_dump($result);
+
+?>
+--CLEAN--
+<?php
+require_once getenv('REDIR_TEST_DIR') . 'pdo_test.inc';
+$db = PDOTest::factory();
+PDOTest::dropTableIfExists($db, "pdo_fetch_function_with_uniqueness_and_grouping");
+?>
+--EXPECT--
+to_upper_with_log('alpha')
+to_upper_with_log('beta')
+to_upper_with_log('gamma')
+to_upper_with_log('delta')
+array(2) {
+  ["Group1"]=>
+  string(4) "BETA"
+  ["Group2"]=>
+  string(5) "DELTA"
+}
diff --git a/ext/pdo/tests/pdo_test.inc b/ext/pdo/tests/pdo_test.inc
index 0c5d5412a273f..8cd60f68aa519 100644
--- a/ext/pdo/tests/pdo_test.inc
+++ b/ext/pdo/tests/pdo_test.inc
@@ -96,4 +96,5 @@ class PDOTest {
         };
     }
 }
+
 ?>
diff --git a/ext/pdo_sqlite/tests/pdo_fetch_func_001.phpt b/ext/pdo_sqlite/tests/pdo_fetch_func_001.phpt
deleted file mode 100644
index e9c2c7e5d5e4b..0000000000000
--- a/ext/pdo_sqlite/tests/pdo_fetch_func_001.phpt
+++ /dev/null
@@ -1,151 +0,0 @@
---TEST--
-Testing several callbacks using PDO::FETCH_FUNC
---EXTENSIONS--
-pdo_sqlite
---FILE--
-<?php
-
-$db = new PDO('sqlite::memory:');
-$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING);
-
-$db->exec('CREATE TABLE test_fetch_func_001 (id INTEGER , name VARCHAR)');
-$db->exec('INSERT INTO test_fetch_func_001 VALUES(1, "php"), (2, "")');
-
-$st = $db->query('SELECT * FROM test_fetch_func_001');
-$st->fetchAll(
-    PDO::FETCH_FUNC,
-    function($x, $y) use ($st) {
-        var_dump($st, $x, $y);
-    }
-);
-
-$st = $db->query('SELECT name FROM test_fetch_func_001');
-var_dump($st->fetchAll(PDO::FETCH_FUNC, 'strtoupper'));
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, 'nothing'));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, ''));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, NULL));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, 1));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, array('self', 'foo')));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-class foo {
-    public function method($x) {
-        return "--- $x ---";
-    }
-}
-class bar extends foo {
-    public function __construct($db) {
-        $st = $db->query('SELECT * FROM test_fetch_func_001');
-        var_dump($st->fetchAll(PDO::FETCH_FUNC, array($this, 'parent::method')));
-    }
-
-    static public function test1($x, $y) {
-        return $x .'---'. $y;
-    }
-
-    private function test2($x, $y) {
-        return $x;
-    }
-
-    public function test3($x, $y) {
-        return $x .'==='. $y;
-    }
-}
-
-new bar($db);
-
-$st = $db->query('SELECT * FROM test_fetch_func_001');
-var_dump($st->fetchAll(PDO::FETCH_FUNC, array('bar', 'test1')));
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, array('bar', 'test2')));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, array('bar', 'test3')));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-try {
-    $st = $db->query('SELECT * FROM test_fetch_func_001');
-    var_dump($st->fetchAll(PDO::FETCH_FUNC, array('bar', 'inexistent')));
-} catch (\TypeError $e) {
-    echo $e->getMessage(), \PHP_EOL;
-}
-
-?>
---EXPECTF--
-object(PDOStatement)#%d (1) {
-  ["queryString"]=>
-  string(33) "SELECT * FROM test_fetch_func_001"
-}
-int(1)
-string(3) "php"
-object(PDOStatement)#%d (1) {
-  ["queryString"]=>
-  string(33) "SELECT * FROM test_fetch_func_001"
-}
-int(2)
-string(0) ""
-array(2) {
-  [0]=>
-  string(3) "PHP"
-  [1]=>
-  string(0) ""
-}
-function "nothing" not found or invalid function name
-function "" not found or invalid function name
-PDOStatement::fetchAll(): Argument #2 must be a callable, null given
-no array or string given
-cannot access "self" when no class scope is active
-
-Deprecated: Callables of the form ["bar", "parent::method"] are deprecated in %s on line %d
-array(2) {
-  [0]=>
-  string(9) "--- 1 ---"
-  [1]=>
-  string(9) "--- 2 ---"
-}
-array(2) {
-  [0]=>
-  string(7) "1---php"
-  [1]=>
-  string(4) "2---"
-}
-non-static method bar::test2() cannot be called statically
-non-static method bar::test3() cannot be called statically
-class bar does not have a method "inexistent"