diff --git a/README.md b/README.md
index 59d30b9..3abc3c3 100644
--- a/README.md
+++ b/README.md
@@ -183,14 +183,15 @@ let rows = yield db.select('table-name');
 ```js
 let rows = yield db.select('table-name', {
   where: {
-    type: 'javascript'
+    type: 'javascript',
+    date: [{ op: '>=', value: '20170504'}]
   },
   columns: ['author', 'title'],
   orders: [['id', 'desc']]
 });
 
 => SELECT `author`, `title` FROM `table-name`
- WHERE `type` = 'javascript' ORDER BY `id` DESC
+ WHERE `type` = 'javascript' AND `date` >= '20170504' ORDER BY `id` DESC
 ```
 
 ### Delete
diff --git a/lib/operator.js b/lib/operator.js
index fc4243b..99755f1 100644
--- a/lib/operator.js
+++ b/lib/operator.js
@@ -191,18 +191,27 @@ proto._where = function(where) {
   for (const key in where) {
     const value = where[key];
     if (Array.isArray(value)) {
-      wheres.push('?? IN (?)');
+      if (value.length > 0 && typeof value[0] === 'object') {
+        for (let i = 0; i < value.length; i++) {
+          wheres.push('?? ' + value[i].op + ' ?');
+          values.push(key);
+          values.push(value[i].value);
+        }
+      } else {
+        wheres.push('?? IN (?)');
+        values.push(key);
+        values.push(value);
+      }
     } else {
       wheres.push('?? = ?');
+      values.push(key);
+      values.push(value);
     }
-    values.push(key);
-    values.push(value);
   }
   if (wheres.length > 0) {
     return this.format(' WHERE ' + wheres.join(' AND '), values);
   }
   return '';
-
 };
 
 proto._selectColumns = function(table, columns) {