Merge pull request #605 from pingcap/coocood/session-autocommit

tidb: set session variable when load from global variable.

bench_test.go

@@ -0,0 +1,30 @@
+package tidb
+
+import (
+	"testing"
+
+	"github.com/ngaut/log"
+)
+
+func BenchmarkBasic(b *testing.B) {
+	store, err := NewStore("memory://bench")
+	if err != nil {
+		b.Fatal(err)
+	}
+	log.SetLevel(log.LOG_LEVEL_ERROR)
+	se, err := CreateSession(store)
+	if err != nil {
+		b.Fatal(err)
+	}
+	for i := 0; i < b.N; i++ {
+		rs, err := se.Execute("select 1")
+		if err != nil {
+			b.Fatal(err)
+		}
+		row, err := rs[0].Next()
+		if err != nil || row == nil {
+			b.Fatal(err)
+		}
+		rs[0].Close()
+	}
+}

session.go

@@ -355,6 +355,7 @@ func (s *session) isAutocommit(ctx context.Context) bool {
 			log.Errorf("Get global sys var error: %v", err)
 			return false
 		}
+		variable.GetSessionVars(ctx).Systems["autocommit"] = autocommit
 		ok = true
 	}
 	if ok && (autocommit == "ON" || autocommit == "on" || autocommit == "1") {