增加随机排序支持

library/think/db/driver/mysql.php

@@ -107,4 +107,14 @@ class Mysql extends Driver
         return $key;
     }
 
+
+    /**
+     * 随机排序
+     * @access protected
+     * @return string
+     */
+    protected function parseRand()
+    {
+        return 'rand()';
+    }
 }

library/think/db/driver/oracle.php

@@ -189,4 +189,14 @@ class Oracle extends Driver
         }
         return $key;
     }
+
+    /**
+     * 随机排序
+     * @access protected
+     * @return string
+     */
+    protected function parseRand()
+    {
+        return 'DBMS_RANDOM.value';
+    }
 }

library/think/db/driver/pgsql.php

@@ -110,4 +110,14 @@ class Pgsql extends Driver
         }
         return $key;
     }
+
+    /**
+     * 随机排序
+     * @access protected
+     * @return string
+     */
+    protected function parseRand()
+    {
+        return 'RANDOM()';
+    }
 }

library/think/db/driver/sqlite.php

@@ -91,4 +91,14 @@ class Sqlite extends Driver
         }
         return $limitStr;
     }
+
+    /**
+     * 随机排序
+     * @access protected
+     * @return string
+     */
+    protected function parseRand()
+    {
+        return 'RANDOM()';
+    }
 }

library/think/db/driver/sqlsrv.php

@@ -93,24 +93,13 @@ class Sqlsrv extends Driver
     }
 
     /**
-     * order分析
+     * 随机排序
      * @access protected
-     * @param mixed $order
      * @return string
      */
-    protected function parseOrder($order)
+    protected function parseRand()
     {
-        $array = [];
-        foreach ($order as $key => $val) {
-            if (is_numeric($key)) {
-                $array[] = $this->parseKey($val);
-            } else {
-                $sort    = in_array(strtolower(trim($val)), ['asc', 'desc']) ? ' ' . $val : '';
-                $array[] = $this->parseKey($key) . ' ' . $sort;
-            }
-        }
-        $order = implode(',', $array);
-        return !empty($order) ? ' ORDER BY ' . $order : ' ORDER BY rand()';
+        return 'rand()';
     }
 
     /**