docs(database): refine lockForUpdate driver warnings

Signed-off-by: memleakd <121398829+memleakd@users.noreply.github.com>

Author: memleakd

system/Database/SQLSRV/Builder.php

@@ -79,10 +79,6 @@ protected function _fromTables(): string
 
         foreach ($this->QBFrom as $value) {
             if (str_starts_with($value, '(SELECT')) {
-                if ($this->QBLockForUpdate) {
-                    throw new DatabaseException('SQLSRV does not support lockForUpdate() on subqueries.');
-                }
-
                 $from[] = $value;
 
                 continue;
@@ -699,10 +695,20 @@ protected function compileSelect($selectOverride = false): string
      */
     protected function compileLockForUpdate(): string
     {
-        if ($this->QBLockForUpdate && $this->QBFrom === []) {
+        if (! $this->QBLockForUpdate) {
+            return '';
+        }
+
+        if ($this->QBFrom === []) {
             throw new DatabaseException('SQLSRV does not support lockForUpdate() without a FROM table.');
         }
 
+        foreach ($this->QBFrom as $value) {
+            if (str_starts_with($value, '(SELECT')) {
+                throw new DatabaseException('SQLSRV does not support lockForUpdate() on subqueries.');
+            }
+        }
+
         return '';
     }
 

user_guide_src/source/database/query_builder.rst

@@ -780,13 +780,13 @@ This method is supported by the **MySQLi**, **Postgre**, **OCI8**, and
 **SQLSRV** drivers. Unsupported drivers throw a ``DatabaseException``. See the
 following notes for OCI8 and SQLSRV driver-specific behavior.
 
-.. note:: SQLSRV uses SQL Server table hints instead of a trailing ``FOR UPDATE``
+.. warning:: SQLSRV uses SQL Server table hints instead of a trailing ``FOR UPDATE``
     clause. The hint is applied to table references in the ``FROM`` clause;
     joined tables are not hinted. Its exact lock granularity depends on SQL
     Server's execution plan and transaction isolation level. SQLSRV does not
     support ``lockForUpdate()`` without a ``FROM`` table or on subqueries.
 
-.. note:: OCI8 does not support ``lockForUpdate()`` together with ``limit()`` or
+.. warning:: OCI8 does not support ``lockForUpdate()`` together with ``limit()`` or
     ``offset()`` because Oracle does not allow ``FOR UPDATE`` with row
     limiting.