diff --git a/tests/pytest/concurrent_inquiry.py b/tests/pytest/concurrent_inquiry.py
index 8ae74c5c863a9dcb5521fc9447f51aa13e7c4c1d..52ae33cfa7918d1b138657d6446bcf36f0de6ee9 100644
--- a/tests/pytest/concurrent_inquiry.py
+++ b/tests/pytest/concurrent_inquiry.py
@@ -166,7 +166,7 @@ class ConcurrentInquiry:
         sel_col_list=[]
         col_rand=random.randint(0,len(col_list))
         for i,j in zip(col_list[0:col_rand],func_list):         #决定每个被查询col的函数
-            alias = 'as '+ str(i)
+            alias = ' as '+ str(i)
             pick_func = ''
             if j == 'leastsquares':
                 pick_func=j+'('+i+',1,1)'
diff --git a/tests/pytest/query/queryNullValueTest.py b/tests/pytest/query/queryNullValueTest.py
index bc0b11827e18b0b436edac1cee2f04bafb05fab3..9920543b3a8d78363197a632eabe47ac6f82fa2e 100644
--- a/tests/pytest/query/queryNullValueTest.py
+++ b/tests/pytest/query/queryNullValueTest.py
@@ -50,7 +50,7 @@ class TDTestCase:
             tdSql.execute("insert into t0 values (%d, NULL)" % (self.ts))
             
             tdDnodes.stop(1)
-            tdLog.sleep(10)
+            # tdLog.sleep(10)
             tdDnodes.start(1)
             tdSql.execute("use db")
             tdSql.query("select * from t0")
@@ -62,7 +62,7 @@ class TDTestCase:
             tdSql.execute("create table t1 (ts timestamp, col %s)" % self.types[i])
             tdSql.execute("insert into t1 values (%d, NULL)" % (self.ts))
             tdDnodes.stop(1)
-            tdLog.sleep(10)
+            # tdLog.sleep(10)
             tdDnodes.start(1)
             tdSql.execute("use db")
 
diff --git a/tests/pytest/update/append_commit_data.py b/tests/pytest/update/append_commit_data.py
index 3169b748e0843c720beb54eced28a14f1ca747a6..867ee696a261936e0118250995da4da5dca7ffb5 100644
--- a/tests/pytest/update/append_commit_data.py
+++ b/tests/pytest/update/append_commit_data.py
@@ -38,38 +38,62 @@ class TDTestCase:
 
         insertRows = 200
         t0 = 1604298064000
+        sql='insert into db.t1 values '
+        temp=''
         tdLog.info("insert %d rows" % (insertRows))
         for i in range(0, insertRows):
-          ret = tdSql.execute(
-              'insert into t1 values (%d , 1)' %
-              (t0+i))
+          # ret = tdSql.execute(
+          #     'insert into t1 values (%d , 1)' %
+          #     (t0+i))
+          temp += '(%d,1)' %(t0+i)
+          if i % 100 == 0 or i == (insertRows - 1 ):
+            print(sql+temp)
+            ret = tdSql.execute(
+                sql+temp
+            )
+            temp = ''
         print("==========step2")
         print("restart to commit ")
         tdDnodes.stop(1)
         tdDnodes.start(1)
         tdSql.query("select * from db.t1")
         tdSql.checkRows(insertRows)
+        
         for k in range(0,100):
           tdLog.info("insert %d rows" % (insertRows))
+          temp=''
           for i in range (0,insertRows):
-            ret = tdSql.execute(
-                'insert into db.t1 values(%d,1)' %
-                (t0+k*200+i)
-            )
+            temp += '(%d,1)' %(t0+k*200+i)
+            if i % 100 == 0 or i == (insertRows - 1 ):
+              print(sql+temp)
+              ret = tdSql.execute(
+                  sql+temp
+              )
+              temp = ''
+            
           tdDnodes.stop(1)
           tdDnodes.start(1)
           tdSql.query("select * from db.t1")
           tdSql.checkRows(insertRows+200*k)
-        print("==========step2")
+        print("==========step3")
         print("insert into another table ")
         s = 'use db'
         tdSql.execute(s)
         ret = tdSql.execute('create table t2 (ts timestamp, a int)')
         insertRows = 20000
+        sql = 'insert into t2 values '
+        temp = ''
         for i in range(0, insertRows):
-          ret = tdSql.execute(
-              'insert into t2 values (%d, 1)' %
-              (t0+i))
+          # ret = tdSql.execute(
+          #     'insert into t2 values (%d, 1)' %
+          #     (t0+i))
+          temp += '(%d,1)' %(t0+i)
+          if i % 500 == 0 or i == (insertRows - 1 ):
+            print(sql+temp)
+            ret = tdSql.execute(
+                sql+temp
+            )
+            temp = ''
         tdDnodes.stop(1)
         tdDnodes.start(1)
         tdSql.query("select * from t2")
diff --git a/tests/pytest/util/dnodes.py b/tests/pytest/util/dnodes.py
index 757399b4a262dff7b11619791d3c82686fb293e8..ed4fcf754fb00d5bae3f8927f091f744b5b33551 100644
--- a/tests/pytest/util/dnodes.py
+++ b/tests/pytest/util/dnodes.py
@@ -255,9 +255,19 @@ class TDDnode:
             tdLog.exit(cmd)
         self.running = 1
         tdLog.debug("dnode:%d is running with %s " % (self.index, cmd))
-
-        tdLog.debug("wait 5 seconds for the dnode:%d to start." % (self.index))
-        time.sleep(5)
+        time.sleep(0.1)
+        key = 'from offline to online'
+        bkey = bytes(key,encoding="utf8")
+        logFile = self.logDir + "/taosdlog.0"
+        popen = subprocess.Popen('tail -f ' + logFile, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
+        while True:
+            line = popen.stdout.readline().strip()
+            if bkey in line:
+                popen.kill()
+                break
+        tdLog.debug("the dnode:%d has been started." % (self.index))
+        
+        # time.sleep(5)
     
     def startWithoutSleep(self):
         buildPath = self.getBuildPath()