diff --git a/context_cache.go b/context_cache.go
index cfe4f17f..1bc22884 100644
--- a/context_cache.go
+++ b/context_cache.go
@@ -6,7 +6,7 @@ package xorm
 
 // ContextCache is the interface that operates the cache data.
 type ContextCache interface {
-	// Put puts value into cache with key and expire time.
+	// Put puts value into cache with key.
 	Put(key string, val interface{})
 	// Get gets cached value by given key.
 	Get(key string) interface{}
@@ -14,14 +14,17 @@ type ContextCache interface {
 
 type memoryContextCache map[string]interface{}
 
+// NewMemoryContextCache return memoryContextCache
 func NewMemoryContextCache() memoryContextCache {
 	return make(map[string]interface{})
 }
 
+// Put puts value into cache with key.
 func (m memoryContextCache) Put(key string, val interface{}) {
 	m[key] = val
 }
 
+// Get gets cached value by given key.
 func (m memoryContextCache) Get(key string) interface{} {
 	return m[key]
 }