fix: Connection::getFieldData() default value convention for SQLSRV and OCI8

system/Database/OCI8/Connection.php

@@ -349,12 +349,25 @@ protected function _fieldData(string $table): array
             $retval[$i]->max_length = $length;
 
             $retval[$i]->nullable = $query[$i]->NULLABLE === 'Y';
-            $retval[$i]->default  = $query[$i]->DATA_DEFAULT;
+            $retval[$i]->default  = $this->normalizeDefault($query[$i]->DATA_DEFAULT);
         }
 
         return $retval;
     }
 
+    /**
+     * Removes trailing whitespace from default values
+     * returned in database column metadata queries.
+     */
+    private function normalizeDefault(?string $default): ?string
+    {
+        if ($default === null) {
+            return $default;
+        }
+
+        return rtrim($default);
+    }
+
     /**
      * Returns an array of objects with index data
      *

system/Database/SQLSRV/Connection.php

@@ -384,12 +384,42 @@ protected function _fieldData(string $table): array
                 );
 
             $retVal[$i]->nullable = $query[$i]->IS_NULLABLE !== 'NO';
-            $retVal[$i]->default  = $query[$i]->COLUMN_DEFAULT;
+            $retVal[$i]->default  = $this->normalizeDefault($query[$i]->COLUMN_DEFAULT);
         }
 
         return $retVal;
     }
 
+    /**
+     * Normalizes SQL Server COLUMN_DEFAULT values.
+     * Removes wrapping parentheses and handles basic conversions.
+     */
+    private function normalizeDefault(?string $default): ?string
+    {
+        if ($default === null) {
+            return null;
+        }
+
+        $default = trim($default);
+
+        // Remove outer parentheses (handles both single and double wrapping)
+        while (preg_match('/^\((.*)\)$/', $default, $matches)) {
+            $default = trim($matches[1]);
+        }
+
+        // Handle NULL literal
+        if (strcasecmp($default, 'NULL') === 0) {
+            return null;
+        }
+
+        // Handle string literals - remove quotes and unescape
+        if (preg_match("/^'(.*)'$/s", $default, $matches)) {
+            return str_replace("''", "'", $matches[1]);
+        }
+
+        return $default;
+    }
+
     /**
      * Begin Transaction
      */

tests/system/Database/Live/ForgeTest.php

@@ -1093,7 +1093,7 @@ public function testAddFields(): void
                     'type'       => 'int',
                     'max_length' => 10,
                     'nullable'   => false,
-                    'default'    => '((0))', // Why?
+                    'default'    => '0',
                 ],
             ];
         } elseif ($this->db->DBDriver === 'OCI8') {
@@ -1124,7 +1124,7 @@ public function testAddFields(): void
                     'type'       => 'NUMBER',
                     'max_length' => '11',
                     'nullable'   => false,
-                    'default'    => '0 ', // Why?
+                    'default'    => '0',
                 ],
             ];
 

tests/system/Database/Live/SQLSRV/GetFieldDataTestCase.php

@@ -14,7 +14,9 @@
 namespace CodeIgniter\Database\Live\SQLSRV;
 
 use CodeIgniter\Database\Live\AbstractGetFieldDataTestCase;
+use CodeIgniter\Database\SQLSRV\Connection;
 use Config\Database;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 
 /**
@@ -68,31 +70,31 @@ public function testGetFieldDataDefault(): void
                 'type'       => 'int',
                 'max_length' => 10,
                 'nullable'   => false,
-                'default'    => '((0))', // int 0
+                'default'    => '0',
                 // 'primary_key' => 0,
             ],
             (object) [
                 'name'       => 'text_default_null',
                 'type'       => 'varchar',
                 'max_length' => 64,
                 'nullable'   => true,
-                'default'    => '(NULL)', // NULL value
+                'default'    => null,
                 // 'primary_key' => 0,
             ],
             (object) [
                 'name'       => 'text_default_text_null',
                 'type'       => 'varchar',
                 'max_length' => 64,
                 'nullable'   => false,
-                'default'    => "('null')", // string "null"
+                'default'    => 'null', // string "null"
                 // 'primary_key' => 0,
             ],
             (object) [
                 'name'       => 'text_default_abc',
                 'type'       => 'varchar',
                 'max_length' => 64,
                 'nullable'   => false,
-                'default'    => "('abc')", // string "abc"
+                'default'    => 'abc',
                 // 'primary_key' => 0,
             ],
         ];
@@ -235,4 +237,58 @@ public function testGetFieldDataType(): void
         ];
         $this->assertSameFieldData($expected, $fields);
     }
+
+    #[DataProvider('provideNormalizeDefault')]
+    public function testNormalizeDefault(?string $input, ?string $expected): void
+    {
+        $this->assertInstanceOf(Connection::class, $this->db);
+
+        $normalizeDefault = self::getPrivateMethodInvoker($this->db, 'normalizeDefault');
+        $this->assertSame($expected, $normalizeDefault($input));
+    }
+
+    /**
+     * @return iterable<string, array{string|null, string|null}>
+     */
+    public static function provideNormalizeDefault(): iterable
+    {
+        return [
+            // Null cases
+            'null input'                          => [null, null],
+            'NULL literal wrapped in parentheses' => ['(NULL)', null],
+            'null literal lowercase'              => ['(null)', null],
+            'null literal mixed case'             => ['(Null)', null],
+            'null literal random case'            => ['(nULL)', null],
+            'null string'                         => ["('null')", 'null'],
+
+            // String literal cases
+            'simple string'                       => ["('hello')", 'hello'],
+            'empty string'                        => ['(())', ''],
+            'string with space'                   => ["('hello world')", 'hello world'],
+            'empty string literal'                => ["('')", ''],
+            'string with escaped quote'           => ["('can''t')", "can't"],
+            'string with multiple escaped quotes' => ["('it''s a ''test''')", "it's a 'test'"],
+            'concatenated multiline expression'   => ["('line1'+char(10)+'line2')", "line1'+char(10)+'line2"],
+
+            // Numeric cases
+            'zero with double parentheses'             => ['((0))', '0'],
+            'positive integer with double parentheses' => ['((123))', '123'],
+            'negative integer with double parentheses' => ['((-456))', '-456'],
+            'float with double parentheses'            => ['((3.14))', '3.14'],
+
+            // Function/expression cases
+            'function call'             => ['(getdate())', 'getdate()'],
+            'newid function'            => ['(newid())', 'newid()'],
+            'user_name function'        => ['(user_name())', 'user_name()'],
+            'current_timestamp'         => ['(current_timestamp)', 'current_timestamp'],
+            'mathematical expression'   => ['((1+1))', '1+1'],
+            'multiplication expression' => ['((100*2))', '100*2'],
+
+            // Edge cases
+            'multiple nested parentheses' => ["((('nested')))", 'nested'],
+            'value without parentheses'   => ['plain_value', 'plain_value'],
+            'value with parentheses'      => ['(  plain_value  )', 'plain_value'],
+            'function with parameters'    => ['(complex_func(1, 2))', 'complex_func(1, 2)'],
+        ];
+    }
 }

user_guide_src/source/changelogs/v4.6.4.rst

@@ -31,6 +31,7 @@ Bugs Fixed
 **********
 
 - **Database:** Fixed a bug in ``Database::connect()`` which was causing to store non-shared connection instances in shared cache.
+- **Database:** Fixed a bug in ``Connection::getFieldData()`` for ``SQLSRV`` and ``OCI8`` where extra characters were returned in column default values (specific to those handlers), instead of following the convention used by other drivers.
 
 See the repo's
 `CHANGELOG.md <https://github.com/codeigniter4/CodeIgniter4/blob/develop/CHANGELOG.md>`_