diff --git a/library/think/model/Relation.php b/library/think/model/Relation.php
index d7938836..22223281 100644
--- a/library/think/model/Relation.php
+++ b/library/think/model/Relation.php
@@ -11,6 +11,8 @@
 
 namespace think\model;
 
+use think\db\Query;
+
 abstract class Relation
 {
     // 父模型对象
@@ -31,6 +33,8 @@ abstract class Relation
     protected $where;
     // 关联查询参数
     protected $option;
+    // 基础查询
+    protected $baseQuery;
 
     /**
      * 获取关联的所属模型
@@ -77,12 +81,16 @@ abstract class Relation
     public function __call($method, $args)
     {
         if ($this->query) {
+            // 执行基础查询
+            $this->baseQuery();
+
             $result = call_user_func_array([$this->query, $method], $args);
-            if ($result instanceof \think\db\Query) {
+            if ($result instanceof Query) {
                 $this->option = $result->getOptions();
                 return $this;
             } else {
-                $this->option = [];
+                $this->option    = [];
+                $this->baseQuery = false;
                 return $result;
             }
         } else {
diff --git a/library/think/model/relation/BelongsTo.php b/library/think/model/relation/BelongsTo.php
index ae5c400e..ffab752d 100644
--- a/library/think/model/relation/BelongsTo.php
+++ b/library/think/model/relation/BelongsTo.php
@@ -11,13 +11,10 @@
 
 namespace think\model\relation;
 
-use think\Db;
-use think\db\Query;
-use think\Loader;
 use think\Model;
-use think\model\Relation;
+use think\model\relation\OneToOne;
 
-class BelongsTo extends Relation
+class BelongsTo extends OneToOne
 {
     /**
      * 架构函数
@@ -40,7 +37,10 @@ class BelongsTo extends Relation
         $this->query      = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         $foreignKey = $this->foreignKey;
@@ -48,124 +48,4 @@ class BelongsTo extends Relation
         return $this->query->where($localKey, $this->parent->$foreignKey)->find();
     }
 
-    /**
-     * 预载入关联查询
-     * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
-    {
-        $name  = Loader::parseName(basename(str_replace('\\', '/', $query->getModel())));
-        $alias = isset($this->alias[$name]) ? $this->alias[$name] : $name;
-        if ($first) {
-
-            $table = $query->getTable();
-            $query->table([$table => $alias]);
-            if ($query->getOptions('field')) {
-                $field = $query->getOptions('field');
-                $query->removeOption('field');
-            } else {
-                $field = true;
-            }
-            $query->field($field, false, $table, $alias);
-        }
-
-        // 预载入封装
-        $joinTable = $this->query->getTable();
-        $joinName  = Loader::parseName(basename(str_replace('\\', '/', $this->model)));
-        $joinAlias = isset($this->alias[$joinName]) ? $this->alias[$joinName] : $relation;
-        $query->via($joinAlias);
-
-        $query->join($joinTable . ' ' . $joinAlias, $alias . '.' . $this->foreignKey . '=' . $joinAlias . '.' . $this->localKey, $this->joinType);
-
-        if ($closure) {
-            // 执行闭包查询
-            call_user_func_array($closure, [ & $query]);
-            //指定获取关联的字段
-            //需要在 回调中 调方法 withField 方法，如
-            // $query->where(['id'=>1])->withField('id,name');
-            if ($query->getOptions('with_field')) {
-                $field = $query->getOptions('with_field');
-                $query->removeOption('with_field');
-            }
-        } elseif (isset($this->option['field'])) {
-            $field = $this->option['field'];
-        } else {
-            $field = true;
-        }
-        $query->field($field, false, $joinTable, $joinAlias, $relation . '__');
-    }
-
-    /**
-     * 预载入关联查询 返回数据集
-     * @access public
-     * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
-     * @param string    $class 数据集对象名 为空表示数组
-     * @return array
-     */
-    public function eagerlyResultSet(&$resultSet, $relation)
-    {
-        foreach ($resultSet as $result) {
-            // 模型关联组装
-            $this->match($this->model, $relation, $result);
-        }
-    }
-
-    /**
-     * 预载入关联查询 返回模型对象
-     * @access public
-     * @param Model     $result 数据对象
-     * @param string    $relation 关联名
-     * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
-     */
-    public function eagerlyResult(&$result, $relation)
-    {
-        // 模型关联组装
-        $this->match($this->model, $relation, $result);
-    }
-
-    /**
-     * 一对一 关联模型预查询拼装
-     * @access public
-     * @param string    $model 模型名称
-     * @param string    $relation 关联名
-     * @param Model     $result 模型对象实例
-     * @return void
-     */
-    protected function match($model, $relation, &$result)
-    {
-        // 重新组装模型数据
-        foreach ($result->getData() as $key => $val) {
-            if (strpos($key, '__')) {
-                list($name, $attr) = explode('__', $key, 2);
-                if ($name == $relation) {
-                    $list[$name][$attr] = $val;
-                    unset($result->$key);
-                }
-            }
-        }
-
-        $result->setAttr($relation, !isset($list[$relation]) ? null : (new $model($list[$relation]))->isUpdate(true));
-    }
-
-    /**
-     * 保存（新增）当前关联数据对象
-     * @access public
-     * @param mixed     $data 数据 可以使用数组 关联模型对象 和 关联对象的主键
-     * @return integer
-     */
-    public function save($data)
-    {
-        if ($data instanceof Model) {
-            $data = $data->getData();
-        }
-        // 保存关联表数据
-        $data[$this->foreignKey] = $this->parent->{$this->localKey};
-        $model                   = new $this->model;
-        return $model->save($data);
-    }
 }
diff --git a/library/think/model/relation/BelongsToMany.php b/library/think/model/relation/BelongsToMany.php
index 59220aee..ccb43be4 100644
--- a/library/think/model/relation/BelongsToMany.php
+++ b/library/think/model/relation/BelongsToMany.php
@@ -43,7 +43,10 @@ class BelongsToMany extends Relation
         $this->query      = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         $foreignKey = $this->foreignKey;
@@ -70,25 +73,14 @@ class BelongsToMany extends Relation
     }
 
     /**
-     * 预载入关联查询
-     * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @param bool      $first 是否需要使用基础表
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
-    {
-
-    }
-
-    /**
-     * 预载入关联查询 返回数据集
+     * 预载入关联查询（数据集）
      * @access public
      * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return array
+     * @return void
      */
     public function eagerlyResultSet(&$resultSet, $relation, $subRelation, $closure, $class)
     {
@@ -125,12 +117,14 @@ class BelongsToMany extends Relation
     }
 
     /**
-     * 预载入关联查询 返回模型对象
+     * 预载入关联查询（单个数据）
      * @access public
      * @param Model     $result 数据对象
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
+     * @return void
      */
     public function eagerlyResult(&$result, $relation, $subRelation, $closure, $class)
     {
@@ -304,27 +298,18 @@ class BelongsToMany extends Relation
         }
     }
 
-    public function __call($method, $args)
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
     {
-        static $baseQuery = false;
-        if ($this->query) {
-            if (empty($baseQuery)) {
-                $baseQuery = true;
-                $pk        = $this->parent->getPk();
-                $this->query->join($this->middle . ' pivot', 'pivot.' . $this->foreignKey . '=' . $this->query->getTable() . '.' . $this->query->getPk())->where('pivot.' . $this->localKey, $this->parent->$pk);
-            }
-
-            $result = call_user_func_array([$this->query, $method], $args);
-            if ($result instanceof \think\db\Query) {
-                $this->option = $result->getOptions();
-                return $this;
-            } else {
-                $this->option = [];
-                $baseQuery    = false;
-                return $result;
-            }
-        } else {
-            throw new Exception('method not exists:' . __CLASS__ . '->' . $method);
+        if (empty($this->baseQuery)) {
+            $pk = $this->parent->getPk();
+            $this->query->join($this->middle . ' pivot', 'pivot.' . $this->foreignKey . '=' . $this->query->getTable() . '.' . $this->query->getPk())->where('pivot.' . $this->localKey, $this->parent->$pk);
+            $this->baseQuery = true;
         }
     }
+
 }
diff --git a/library/think/model/relation/HasMany.php b/library/think/model/relation/HasMany.php
index 5c7d129a..7d73e3a2 100644
--- a/library/think/model/relation/HasMany.php
+++ b/library/think/model/relation/HasMany.php
@@ -37,7 +37,10 @@ class HasMany extends Relation
         $this->query      = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         return $this->select();
@@ -46,23 +49,12 @@ class HasMany extends Relation
     /**
      * 预载入关联查询
      * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @param bool      $first 是否需要使用基础表
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
-    {
-
-    }
-
-    /**
-     * 预载入关联查询 返回数据集
-     * @access public
      * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return array
+     * @return void
      */
     public function eagerlyResultSet(&$resultSet, $relation, $subRelation, $closure, $class)
     {
@@ -97,12 +89,14 @@ class HasMany extends Relation
     }
 
     /**
-     * 预载入关联查询 返回模型对象
+     * 预载入关联查询
      * @access public
      * @param Model     $result 数据对象
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
+     * @return void
      */
     public function eagerlyResult(&$result, $relation, $subRelation, $closure, $class)
     {
@@ -221,31 +215,22 @@ class HasMany extends Relation
             ->where($where);
     }
 
-    public function __call($method, $args)
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
     {
-        static $baseQuery = false;
-        if ($this->query) {
-            if (empty($baseQuery)) {
-                $baseQuery = true;
-                if (isset($this->where)) {
-                    $this->query->where($this->where);
-                } elseif (isset($this->parent->{$this->localKey})) {
-                    // 关联查询带入关联条件
-                    $this->query->where($this->foreignKey, $this->parent->{$this->localKey});
-                }
+        if (empty($this->baseQuery)) {
+            if (isset($this->where)) {
+                $this->query->where($this->where);
+            } elseif (isset($this->parent->{$this->localKey})) {
+                // 关联查询带入关联条件
+                $this->query->where($this->foreignKey, $this->parent->{$this->localKey});
             }
-
-            $result = call_user_func_array([$this->query, $method], $args);
-            if ($result instanceof \think\db\Query) {
-                $this->option = $result->getOptions();
-                return $this;
-            } else {
-                $this->option = [];
-                $baseQuery    = false;
-                return $result;
-            }
-        } else {
-            throw new Exception('method not exists:' . __CLASS__ . '->' . $method);
+            $this->baseQuery = true;
         }
     }
+
 }
diff --git a/library/think/model/relation/HasManyThrough.php b/library/think/model/relation/HasManyThrough.php
index 2661b7b3..9f4c0431 100644
--- a/library/think/model/relation/HasManyThrough.php
+++ b/library/think/model/relation/HasManyThrough.php
@@ -45,7 +45,10 @@ class HasManyThrough extends Relation
         $this->query      = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         return $this->select();
@@ -65,12 +68,14 @@ class HasManyThrough extends Relation
     }
 
     /**
-     * 预载入关联查询 返回数据集
+     * 预载入关联查询
      * @access public
      * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return array
+     * @return void
      */
     public function eagerlyResultSet(&$resultSet, $relation, $subRelation, $closure, $class)
     {
@@ -81,45 +86,38 @@ class HasManyThrough extends Relation
      * 预载入关联查询 返回模型对象
      * @access public
      * @param Model     $result 数据对象
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
+     * @return void
      */
     public function eagerlyResult(&$result, $relation, $subRelation, $closure, $class)
     {
 
     }
 
-    public function __call($method, $args)
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
     {
-        static $baseQuery = false;
-        if ($this->query) {
-            if (empty($baseQuery)) {
-                $baseQuery    = true;
-                $through      = $this->middle;
-                $model        = $this->model;
-                $alias        = Loader::parseName(basename(str_replace('\\', '/', $model)));
-                $throughTable = $through::getTable();
-                $pk           = (new $this->model)->getPk();
-                $throughKey   = $this->throughKey;
-                $modelTable   = $this->parent->getTable();
-                $this->query->field($alias . '.*')->alias($alias)
-                    ->join($throughTable, $throughTable . '.' . $pk . '=' . $alias . '.' . $throughKey)
-                    ->join($modelTable, $modelTable . '.' . $this->localKey . '=' . $throughTable . '.' . $this->foreignKey)
-                    ->where($throughTable . '.' . $this->foreignKey, $this->parent->{$this->localKey});
-            }
-
-            $result = call_user_func_array([$this->query, $method], $args);
-            if ($result instanceof \think\db\Query) {
-                $this->option = $result->getOptions();
-                return $this;
-            } else {
-                $this->option = [];
-                $baseQuery    = false;
-                return $result;
-            }
-        } else {
-            throw new Exception('method not exists:' . __CLASS__ . '->' . $method);
+        if (empty($this->baseQuery)) {
+            $through      = $this->middle;
+            $model        = $this->model;
+            $alias        = Loader::parseName(basename(str_replace('\\', '/', $model)));
+            $throughTable = $through::getTable();
+            $pk           = (new $this->model)->getPk();
+            $throughKey   = $this->throughKey;
+            $modelTable   = $this->parent->getTable();
+            $this->query->field($alias . '.*')->alias($alias)
+                ->join($throughTable, $throughTable . '.' . $pk . '=' . $alias . '.' . $throughKey)
+                ->join($modelTable, $modelTable . '.' . $this->localKey . '=' . $throughTable . '.' . $this->foreignKey)
+                ->where($throughTable . '.' . $this->foreignKey, $this->parent->{$this->localKey});
+            $this->baseQuery = true;
         }
     }
+
 }
diff --git a/library/think/model/relation/HasOne.php b/library/think/model/relation/HasOne.php
index c7b71c53..85ac237e 100644
--- a/library/think/model/relation/HasOne.php
+++ b/library/think/model/relation/HasOne.php
@@ -11,13 +11,10 @@
 
 namespace think\model\relation;
 
-use think\Db;
-use think\db\Query;
-use think\Loader;
 use think\Model;
-use think\model\Relation;
+use think\model\relation\OneToOne;
 
-class HasOne extends Relation
+class HasOne extends OneToOne
 {
     /**
      * 架构函数
@@ -40,7 +37,10 @@ class HasOne extends Relation
         $this->query      = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         // 执行关联定义方法
@@ -50,125 +50,4 @@ class HasOne extends Relation
         return $this->query->where($this->foreignKey, $this->parent->$localKey)->find();
     }
 
-    /**
-     * 预载入关联查询
-     * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, &$closure, $first)
-    {
-        $name  = Loader::parseName(basename(str_replace('\\', '/', $query->getModel())));
-        $alias = isset($this->alias[$name]) ? $this->alias[$name] : $name;
-        if ($first) {
-            $table = $query->getTable();
-            $query->table([$table => $alias]);
-            if ($query->getOptions('field')) {
-                $field = $query->getOptions('field');
-                $query->removeOption('field');
-            } else {
-                $field = true;
-            }
-            $query->field($field, false, $table, $alias);
-
-        }
-
-        // 预载入封装
-        $joinTable = $this->query->getTable();
-        $joinName  = Loader::parseName(basename(str_replace('\\', '/', $this->model)));
-        $joinAlias = isset($this->alias[$joinName]) ? $this->alias[$joinName] : $relation;
-        $query->via($joinAlias);
-
-        $query->join($joinTable . ' ' . $joinAlias, $alias . '.' . $this->localKey . '=' . $joinAlias . '.' . $this->foreignKey, $this->joinType);
-
-        if ($closure) {
-            // 执行闭包查询
-            call_user_func_array($closure, [ & $query]);
-            //指定获取关联的字段
-            //需要在 回调中 调方法 withField 方法，如
-            // $query->where(['id'=>1])->withField('id,name');
-            if ($query->getOptions('with_field')) {
-                $field = $query->getOptions('with_field');
-                $query->removeOption('with_field');
-            }
-            $closure = null;
-        } elseif (isset($this->option['field'])) {
-            $field = $this->option['field'];
-        } else {
-            $field = true;
-        }
-        $query->field($field, false, $joinTable, $joinAlias, $relation . '__');
-    }
-
-    /**
-     * 预载入关联查询 返回数据集
-     * @access public
-     * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
-     * @param string    $class 数据集对象名 为空表示数组
-     * @return array
-     */
-    public function eagerlyResultSet(&$resultSet, $relation)
-    {
-        foreach ($resultSet as $result) {
-            // 模型关联组装
-            $this->match($this->model, $relation, $result);
-        }
-    }
-
-    /**
-     * 预载入关联查询 返回模型对象
-     * @access public
-     * @param Model     $result 数据对象
-     * @param string    $relation 关联名
-     * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
-     */
-    public function eagerlyResult(&$result, $relation)
-    {
-        // 模型关联组装
-        $this->match($this->model, $relation, $result);
-    }
-
-    /**
-     * 一对一 关联模型预查询拼装
-     * @access public
-     * @param string    $model 模型名称
-     * @param string    $relation 关联名
-     * @param Model     $result 模型对象实例
-     * @return void
-     */
-    protected function match($model, $relation, &$result)
-    {
-        // 重新组装模型数据
-        foreach ($result->getData() as $key => $val) {
-            if (strpos($key, '__')) {
-                list($name, $attr) = explode('__', $key, 2);
-                if ($name == $relation) {
-                    $list[$name][$attr] = $val;
-                    unset($result->$key);
-                }
-            }
-        }
-
-        $result->setAttr($relation, !isset($list[$relation]) ? null : (new $model($list[$relation]))->isUpdate(true));
-    }
-
-    /**
-     * 保存（新增）当前关联数据对象
-     * @access public
-     * @param mixed     $data 数据 可以使用数组 关联模型对象 和 关联对象的主键
-     * @return integer
-     */
-    public function save($data)
-    {
-        if ($data instanceof Model) {
-            $data = $data->getData();
-        }
-        // 保存关联表数据
-        $data[$this->foreignKey] = $this->parent->{$this->localKey};
-        $model                   = new $this->model;
-        return $model->save($data);
-    }
 }
diff --git a/library/think/model/relation/MorphMany.php b/library/think/model/relation/MorphMany.php
index 9d6371ba..cfce9b57 100644
--- a/library/think/model/relation/MorphMany.php
+++ b/library/think/model/relation/MorphMany.php
@@ -43,7 +43,10 @@ class MorphMany extends Relation
         $this->query     = (new $model)->db();
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         return $this->select();
@@ -52,23 +55,12 @@ class MorphMany extends Relation
     /**
      * 预载入关联查询
      * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @param bool      $first 是否需要使用基础表
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
-    {
-
-    }
-
-    /**
-     * 预载入关联查询 返回数据集
-     * @access public
      * @param array     $resultSet 数据集
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return array
+     * @return void
      */
     public function eagerlyResultSet(&$resultSet, $relation, $subRelation, $closure, $class)
     {
@@ -103,12 +95,14 @@ class MorphMany extends Relation
     }
 
     /**
-     * 预载入关联查询 返回模型对象
+     * 预载入关联查询
      * @access public
      * @param Model     $result 数据对象
-     * @param string    $relation 关联名
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
      * @param string    $class 数据集对象名 为空表示数组
-     * @return Model
+     * @return void
      */
     public function eagerlyResult(&$result, $relation, $subRelation, $closure, $class)
     {
@@ -147,29 +141,20 @@ class MorphMany extends Relation
         return $data;
     }
 
-    public function __call($method, $args)
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
     {
-        static $baseQuery = false;
-        if ($this->query) {
-            if (empty($baseQuery)) {
-                $baseQuery             = true;
-                $pk                    = $this->parent->getPk();
-                $map[$this->morphKey]  = $this->parent->$pk;
-                $map[$this->morphType] = $this->type;
-                $this->query->where($map);
-            }
-
-            $result = call_user_func_array([$this->query, $method], $args);
-            if ($result instanceof \think\db\Query) {
-                $this->option = $result->getOptions();
-                return $this;
-            } else {
-                $this->option = [];
-                $baseQuery    = false;
-                return $result;
-            }
-        } else {
-            throw new Exception('method not exists:' . __CLASS__ . '->' . $method);
+        if (empty($this->baseQuery)) {
+            $pk                    = $this->parent->getPk();
+            $map[$this->morphKey]  = $this->parent->$pk;
+            $map[$this->morphType] = $this->type;
+            $this->query->where($map);
+            $this->baseQuery = true;
         }
     }
+
 }
diff --git a/library/think/model/relation/MorphTo.php b/library/think/model/relation/MorphTo.php
index 0d55d2e4..2b370e08 100644
--- a/library/think/model/relation/MorphTo.php
+++ b/library/think/model/relation/MorphTo.php
@@ -11,7 +11,6 @@
 
 namespace think\model\relation;
 
-use think\db\Query;
 use think\Loader;
 use think\Model;
 use think\model\Relation;
@@ -38,7 +37,10 @@ class MorphTo extends Relation
         $this->alias     = $alias;
     }
 
-    // 动态获取关联数据
+    /**
+     * 延迟获取关联数据
+     * @access public
+     */
     public function getRelation()
     {
         $morphKey  = $this->morphKey;
@@ -70,19 +72,6 @@ class MorphTo extends Relation
         return $model;
     }
 
-    /**
-     * 预载入关联查询
-     * @access public
-     * @param Query     $query 查询对象
-     * @param string    $relation 关联名
-     * @param bool      $first 是否需要使用基础表
-     * @return void
-     */
-    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
-    {
-
-    }
-
     /**
      * 预载入关联查询 返回数据集
      * @access public
@@ -163,4 +152,12 @@ class MorphTo extends Relation
         $result->setAttr($relation, $data ?: null);
     }
 
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
+    {
+    }
 }
diff --git a/library/think/model/relation/OneToOne.php b/library/think/model/relation/OneToOne.php
new file mode 100644
index 00000000..650000e9
--- /dev/null
+++ b/library/think/model/relation/OneToOne.php
@@ -0,0 +1,161 @@
+<?php
+// +----------------------------------------------------------------------
+// | ThinkPHP [ WE CAN DO IT JUST THINK ]
+// +----------------------------------------------------------------------
+// | Copyright (c) 2006~2016 http://thinkphp.cn All rights reserved.
+// +----------------------------------------------------------------------
+// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
+// +----------------------------------------------------------------------
+// | Author: liu21st <liu21st@gmail.com>
+// +----------------------------------------------------------------------
+
+namespace think\model\relation;
+
+use think\db\Query;
+use think\Loader;
+use think\Model;
+use think\model\Relation;
+use think\model\relation\BelongsTo;
+
+abstract class OneToOne extends Relation
+{
+    /**
+     * 预载入关联查询
+     * @access public
+     * @param Query     $query 查询对象
+     * @param string    $relation 关联名
+     * @param string    $subRelation 子关联
+     * @param \Closure  $closure 闭包条件
+     * @param bool      $first
+     * @return void
+     */
+    public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
+    {
+        $name  = Loader::parseName(basename(str_replace('\\', '/', $query->getModel())));
+        $alias = isset($this->alias[$name]) ? $this->alias[$name] : $name;
+        if ($first) {
+            $table = $query->getTable();
+            $query->table([$table => $alias]);
+            if ($query->getOptions('field')) {
+                $field = $query->getOptions('field');
+                $query->removeOption('field');
+            } else {
+                $field = true;
+            }
+            $query->field($field, false, $table, $alias);
+        }
+
+        // 预载入封装
+        $joinTable = $this->query->getTable();
+        $joinName  = Loader::parseName(basename(str_replace('\\', '/', $this->model)));
+        $joinAlias = isset($this->alias[$joinName]) ? $this->alias[$joinName] : $relation;
+        $query->via($joinAlias);
+
+        if ($this instanceof BelongsTo) {
+            $query->join($joinTable . ' ' . $joinAlias, $alias . '.' . $this->foreignKey . '=' . $joinAlias . '.' . $this->localKey, $this->joinType);
+        } else {
+            $query->join($joinTable . ' ' . $joinAlias, $alias . '.' . $this->localKey . '=' . $joinAlias . '.' . $this->foreignKey, $this->joinType);
+        }
+
+        if ($closure) {
+            // 执行闭包查询
+            call_user_func_array($closure, [ & $query]);
+            //指定获取关联的字段
+            //需要在 回调中 调方法 withField 方法，如
+            // $query->where(['id'=>1])->withField('id,name');
+            if ($query->getOptions('with_field')) {
+                $field = $query->getOptions('with_field');
+                $query->removeOption('with_field');
+            }
+        } elseif (isset($this->option['field'])) {
+            $field = $this->option['field'];
+        } else {
+            $field = true;
+        }
+        $query->field($field, false, $joinTable, $joinAlias, $relation . '__');
+    }
+
+    /**
+     * 预载入关联查询
+     * @access public
+     * @param array     $resultSet 数据集
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
+     * @param string    $class 数据集对象名 为空表示数组
+     * @return void
+     */
+    public function eagerlyResultSet(&$resultSet, $relation)
+    {
+        foreach ($resultSet as $result) {
+            // 模型关联组装
+            $this->match($this->model, $relation, $result);
+        }
+    }
+
+    /**
+     * 预载入关联查询 返回模型对象
+     * @access public
+     * @param Model     $result 数据对象
+     * @param string    $relation 当前关联名
+     * @param string    $subRelation 子关联名
+     * @param \Closure  $closure 闭包
+     * @param string    $class 数据集对象名 为空表示数组
+     * @return void
+     */
+    public function eagerlyResult(&$result, $relation)
+    {
+        // 模型关联组装
+        $this->match($this->model, $relation, $result);
+    }
+
+    /**
+     * 一对一 关联模型预查询拼装
+     * @access public
+     * @param string    $model 模型名称
+     * @param string    $relation 关联名
+     * @param Model     $result 模型对象实例
+     * @return void
+     */
+    protected function match($model, $relation, &$result)
+    {
+        // 重新组装模型数据
+        foreach ($result->getData() as $key => $val) {
+            if (strpos($key, '__')) {
+                list($name, $attr) = explode('__', $key, 2);
+                if ($name == $relation) {
+                    $list[$name][$attr] = $val;
+                    unset($result->$key);
+                }
+            }
+        }
+
+        $result->setAttr($relation, !isset($list[$relation]) ? null : (new $model($list[$relation]))->isUpdate(true));
+    }
+
+    /**
+     * 保存（新增）当前关联数据对象
+     * @access public
+     * @param mixed     $data 数据 可以使用数组 关联模型对象 和 关联对象的主键
+     * @return integer
+     */
+    public function save($data)
+    {
+        if ($data instanceof Model) {
+            $data = $data->getData();
+        }
+        // 保存关联表数据
+        $data[$this->foreignKey] = $this->parent->{$this->localKey};
+        $model                   = new $this->model;
+        return $model->save($data);
+    }
+
+    /**
+     * 执行基础查询（进执行一次）
+     * @access protected
+     * @return void
+     */
+    protected function baseQuery()
+    {
+    }
+}