diff --git a/g/database/gdb/gdb.go b/g/database/gdb/gdb.go
index 8eec0cbdf..e66f23931 100644
--- a/g/database/gdb/gdb.go
+++ b/g/database/gdb/gdb.go
@@ -91,7 +91,7 @@ type Db struct {
 	charr            string        // SQL安全符号(右)
 	debug            *gtype.Bool   // (默认关闭)是否开启调试模式，当开启时会启用一些调试特性
 	sqls             *gring.Ring   // (debug=true时有效)已执行的SQL列表
-	cache            *gcache.Cache // 查询缓存，需要注意的是，事务查询不支持缓存
+	cache            *gcache.Cache // 数据库缓存，包括底层连接池对象缓存及查询缓存；需要注意的是，事务查询不支持查询缓存
     maxIdleConnCount *gtype.Int    // 连接池最大限制的连接数
     maxOpenConnCount *gtype.Int    // 连接池最大打开的连接数
     maxConnLifetime  *gtype.Int    // (单位秒)连接对象可重复使用的时间长度
@@ -248,40 +248,51 @@ func getLinkByType(dbType string) (Link, error) {
 }
 
 // 获得底层数据库链接对象
-func (db *Db) getSqlDb(master bool) (*sql.DB, error) {
+func (db *Db) getSqlDb(master bool) (sqlDb *sql.DB, err error) {
+    // 负载均衡
     node, err := getConfigNodeByGroup(db.group, master)
     if err != nil {
         return nil, err
     }
+    // 类型对象
     link, err := getLinkByType(node.Type)
     if err != nil {
         return nil, err
     }
-    sqlDb, err := link.Open(node)
-    if err != nil {
-        return nil, err
-    }
-    if node.MaxIdleConnCount > 0 {
-        sqlDb.SetMaxIdleConns(node.MaxIdleConnCount)
-    }
-    if n := db.maxIdleConnCount.Val(); n > 0 {
-        sqlDb.SetMaxIdleConns(n)
+    // 检查缓存连接池对象
+    cacheKey := node.String()
+    if v := db.cache.Get(cacheKey); v != nil {
+        return v.(*sql.DB), nil
     }
+    v := db.cache.GetOrSetFuncLock(node.String(), func() interface{} {
+        sqlDb, err = link.Open(node)
+        if err != nil {
+            return nil
+        }
 
-    if node.MaxOpenConnCount > 0 {
-        sqlDb.SetMaxOpenConns(node.MaxOpenConnCount)
-    }
-    if n := db.maxOpenConnCount.Val(); n > 0 {
-        sqlDb.SetMaxOpenConns(n)
-    }
+        if n := db.maxIdleConnCount.Val(); n > 0 {
+            sqlDb.SetMaxIdleConns(n)
+        } else if node.MaxIdleConnCount > 0 {
+            sqlDb.SetMaxIdleConns(node.MaxIdleConnCount)
+        }
 
-    if node.MaxConnLifetime > 0 {
-        sqlDb.SetConnMaxLifetime(time.Duration(node.MaxConnLifetime) * time.Second)
+        if n := db.maxOpenConnCount.Val(); n > 0 {
+            sqlDb.SetMaxOpenConns(n)
+        } else if node.MaxOpenConnCount > 0 {
+            sqlDb.SetMaxOpenConns(node.MaxOpenConnCount)
+        }
+
+        if n := db.maxConnLifetime.Val(); n > 0 {
+            sqlDb.SetConnMaxLifetime(time.Duration(n) * time.Second)
+        } else if node.MaxConnLifetime > 0 {
+            sqlDb.SetConnMaxLifetime(time.Duration(node.MaxConnLifetime) * time.Second)
+        }
+        return sqlDb
+    }, 0)
+    if v != nil && sqlDb == nil {
+        sqlDb = v.(*sql.DB)
     }
-    if n := db.maxConnLifetime.Val(); n > 0 {
-        sqlDb.SetConnMaxLifetime(time.Duration(n) * time.Second)
-    }
-    return sqlDb, nil
+    return
 }
 
 // 创建底层数据库master链接对象
diff --git a/g/database/gdb/gdb_base.go b/g/database/gdb/gdb_base.go
index 1cfc1b76b..ade922df1 100644
--- a/g/database/gdb/gdb_base.go
+++ b/g/database/gdb/gdb_base.go
@@ -89,7 +89,6 @@ func (db *Db) Query(query string, args ...interface{}) (*sql.Rows, error) {
     if err != nil {
         return nil,err
     }
-    defer slave.Close()
     p := db.link.handleSqlBeforeExec(&query)
     if db.debug.Val() {
         militime1 := gtime.Millisecond()
@@ -125,7 +124,6 @@ func (db *Db) Exec(query string, args ...interface{}) (sql.Result, error) {
     if err != nil {
         return nil,err
     }
-    defer master.Close()
     p := db.link.handleSqlBeforeExec(&query)
     if db.debug.Val() {
         militime1  := gtime.Millisecond()
@@ -259,12 +257,10 @@ func (db *Db) Select(tables, fields string, condition interface{}, groupBy, orde
 }
 
 // sql预处理，执行完成后调用返回值sql.Stmt.Exec完成sql操作
-// 记得调用sql.Stmt.Close关闭操作对象
 func (db *Db) Prepare(query string) (*sql.Stmt, error) {
     if master, err := db.Master(); err != nil {
         return nil, err
     } else {
-        defer master.Close()
         return master.Prepare(query)
     }
 }
@@ -274,7 +270,6 @@ func (db *Db) PingMaster() error {
     if master, err := db.Master(); err != nil {
         return err
     } else {
-        defer master.Close()
         return master.Ping()
     }
 }
@@ -284,7 +279,6 @@ func (db *Db) PingSlave() error {
     if slave, err := db.Slave(); err != nil {
         return err
     } else {
-        defer slave.Close()
         return slave.Ping()
     }
 }
diff --git a/g/database/gdb/gdb_config.go b/g/database/gdb/gdb_config.go
index f3ed7df33..f3a6f490c 100644
--- a/g/database/gdb/gdb_config.go
+++ b/g/database/gdb/gdb_config.go
@@ -8,6 +8,7 @@
 package gdb
 
 import (
+    "fmt"
     "sync"
 )
 
@@ -134,4 +135,15 @@ func (db *Db) SetMaxOpenConns(n int) {
 // 如果 d <= 0 表示该链接会一直重复利用
 func (db *Db) SetConnMaxLifetime(n int) {
     db.maxConnLifetime.Set(n)
+}
+
+// 节点配置转换为字符串
+func (node *ConfigNode) String() string {
+    if node.Linkinfo != "" {
+        return node.Linkinfo
+    }
+    return fmt.Sprintf(`%s@%s:%s,%s,%s,%s,%s,%d-%d-%d`, node.User, node.Host, node.Port,
+        node.Name, node.Type, node.Role, node.Charset,
+        node.MaxIdleConnCount, node.MaxOpenConnCount, node.MaxConnLifetime,
+    )
 }
\ No newline at end of file
diff --git a/g/database/gdb/gdb_transaction.go b/g/database/gdb/gdb_transaction.go
index a65cffa87..692b3bb5b 100644
--- a/g/database/gdb/gdb_transaction.go
+++ b/g/database/gdb/gdb_transaction.go
@@ -27,16 +27,12 @@ type Tx struct {
 
 // 事务操作，提交
 func (tx *Tx) Commit() error {
-    err := tx.tx.Commit()
-    tx.master.Close()
-    return err
+    return tx.tx.Commit()
 }
 
 // 事务操作，回滚
 func (tx *Tx) Rollback() error {
-    err := tx.tx.Rollback()
-    tx.master.Close()
-    return err
+    return tx.tx.Rollback()
 }
 
 // (事务)数据库sql查询操作，主要执行查询
@@ -193,7 +189,6 @@ func (tx *Tx) Select(tables, fields string, condition interface{}, groupBy, orde
 }
 
 // sql预处理，执行完成后调用返回值sql.Stmt.Exec完成sql操作
-// 记得调用sql.Stmt.Close关闭操作对象
 func (tx *Tx) Prepare(query string) (*sql.Stmt, error) {
     return tx.tx.Prepare(query)
 }
diff --git a/geg/database/orm/mysql/gdb_pool.go b/geg/database/orm/mysql/gdb_pool.go
new file mode 100644
index 000000000..8f4c7dabf
--- /dev/null
+++ b/geg/database/orm/mysql/gdb_pool.go
@@ -0,0 +1,36 @@
+package main
+
+import (
+    "gitee.com/johng/gf/g/database/gdb"
+    "time"
+)
+
+func main() {
+    gdb.AddDefaultConfigNode(gdb.ConfigNode {
+        Host             : "127.0.0.1",
+        Port             : "3306",
+        User             : "root",
+        Pass             : "12345678",
+        Name             : "test",
+        Type             : "mysql",
+        Role             : "master",
+        Charset          : "utf8",
+        MaxIdleConnCount : 10,
+        MaxOpenConnCount : 10,
+        MaxConnLifetime  : 10,
+    })
+    db, err := gdb.New()
+    if err != nil {
+        panic(err)
+    }
+    // 开启调试模式，以便于记录所有执行的SQL
+    db.SetDebug(true)
+
+    for {
+        for i := 0; i < 10; i++ {
+            go db.Table("user").All()
+        }
+        time.Sleep(time.Second)
+    }
+
+}
\ No newline at end of file
diff --git a/geg/database/orm/mysql/gdb_value.go b/geg/database/orm/mysql/gdb_value.go
index ad9a2ba1a..7851f6dd6 100644
--- a/geg/database/orm/mysql/gdb_value.go
+++ b/geg/database/orm/mysql/gdb_value.go
@@ -1,9 +1,8 @@
 package main
 
 import (
-    "gitee.com/johng/gf/g/database/gdb"
     "fmt"
-    "gitee.com/johng/gf/g/encoding/gparser"
+    "gitee.com/johng/gf/g/database/gdb"
 )
 
 func main() {
@@ -27,8 +26,5 @@ func main() {
     r, _ := db.Table("user").All()
     if r != nil {
         fmt.Println(r.ToList())
-        b, e := gparser.VarToJson(r.ToList())
-        fmt.Println(e)
-        fmt.Println(string(b))
     }
 }
\ No newline at end of file