diff --git a/tests/script/unique/clusterSimCase/client-06.sim b/tests/script/unique/clusterSimCase/client-06.sim
index 013eb1db85f6665dd2b5090a0999d1e355ad1e93..209b615e64a2742cac732bd22d0e25f7a8f5db4e 100644
--- a/tests/script/unique/clusterSimCase/client-06.sim
+++ b/tests/script/unique/clusterSimCase/client-06.sim
@@ -9,8 +9,6 @@ $tsStart  = 1325347200000  # 2012-01-01 00:00:00.000
 $preBinary = ' . client-06-
 $numPerUpdateTbl = 2000
 ###############################################################
-$testCnt = 0
-
 $totalRows    = 0  
 $dropTblStart = $tblStart
 $dropTblEnd   = $dropTblStart
@@ -23,7 +21,7 @@ sql create database if not exists $db replica 2
 sql use $db
 
 init_lable:
-print ================ create table $tb [ from $tblStart to $tblEnd ] (ts timestamp, c1 int, c2 binary(16))
+print ================ create table [ from $tblStart to $tblEnd ] (ts timestamp, c1 int, c2 binary(16))
 
 $i = $tblStart
 while $i < $tblEnd
@@ -90,12 +88,8 @@ if $loopCnt > 2 then
     $i = $i + 1
     $totalRows = $totalRows - $rowsPerTbl
   endw  
-  sleep 20000
-  $testCnt = $testCnt + 1
+  sleep 10000
   goto init_lable 
 endi
 
-if $testCnt > 10 then
-  return 0
-endi
 goto loop_run
diff --git a/tests/script/unique/clusterSimCase/client-07.sim b/tests/script/unique/clusterSimCase/client-07.sim
index 0dde62248d53bf1a941b54ada17cee6ed6603f2e..3bf358520511dc04cc33c5953f91bee237ccd576 100644
--- a/tests/script/unique/clusterSimCase/client-07.sim
+++ b/tests/script/unique/clusterSimCase/client-07.sim
@@ -7,6 +7,10 @@ $tblEnd   = 10000
 $tsStart  = 1325347200000  # 2012-01-01 00:00:00.000
 $preBinary = ' . client-07-
 ###############################################################
+$alterCnt = 0
+
+$columnA = c . $alterCnt
+$columnB = d . $alterCnt
 
 $totalRows   = 0
 
@@ -17,22 +21,23 @@ $db = db
 sql create database if not exists $db replica 2 
 sql use $db
 
-init_lable:
-print ================ create table $tb (ts timestamp, c1 int, c2 binary(16))
+$rowsPerTbl  = 0
+$ts          = $tsStart
+
+print ================ create table $tb (ts timestamp, $columnA int, $columnB binary(16))
 
 $i = $tblStart
 while $i < $tblEnd
   $tb = tb . $i
 #  print create table if not exists $tb ( ts timestamp , c1 int , c2 binary(16) )
-  sql create table if not exists $tb ( ts timestamp , c1 int , c2 binary(16) )
+  sql create table if not exists $tb ( ts timestamp , $columnA int , $columnB binary(16) )
   $i = $i + 1
 endw 
 
-$rowsPerTbl  = 0
-$ts          = $tsStart
 $rowsPerLoop = 160
 
 $loopCnt = 0
+$alterStep = 0
  
 loop_run:
 print ================ client-07 start loop insert data ( loopCnt: $loopCnt )
@@ -70,19 +75,27 @@ endi
 
 $loopCnt = $loopCnt + 1
 
-if $loopCnt > 100 then
-
+if $alterStep > 2 then
+  $alterStep = 0
+  
+  $alterCnt = $alterCnt + 1
   $i = $tblStart
   while $i < $tblEnd
     $tb = tb . $i
-    sql alter table $tb add column c3 double
-    sql alter table $tb add column c4 binary( 16 )
-    sql alter table $tb drop column c1
-    sql alter table $tb drop column c2
+    $newColumnA = c . $alterCnt
+    $newcolumnB = d . $alterCnt
+
+    sql alter table $tb add column $newColumnA double
+    sql alter table $tb add column $newcolumnB binary( 16 )
+    sql alter table $tb drop column $columnA
+    sql alter table $tb drop column $columnB
     $i = $i + 1
-  endw  
-  sleep 20000
-  goto init_lable 
+  endw
+  $columnA = $newColumnA
+  $columnB = $newcolumnB
+    
+  sleep 10000
+  goto loop_run 
 endi
 
 goto loop_run
diff --git a/tests/script/unique/clusterSimCase/client-08.sim b/tests/script/unique/clusterSimCase/client-08.sim
index 891b3991b6967debaf70375c1b7ca935bc3184fb..78608b2c42cc17559fdac2c836bfe9c04ed9b3ad 100644
--- a/tests/script/unique/clusterSimCase/client-08.sim
+++ b/tests/script/unique/clusterSimCase/client-08.sim
@@ -4,13 +4,14 @@
 ###############################################################
 ################ set script parameters ################
 $tblStart = 0
-$tblEnd   = 10000
+$tblEnd   = 100
 $tsStart  = 1325347200000  # 2012-01-01 00:00:00.000
 $preBinary = ' . client-08-
-$numPerUpdateTbl = 2000
+$numPerUpdateTbl = 20
 ###############################################################
-
-$totalRows   = 0
+$totalRows    = 0  
+$dropTblStart = $tblStart
+$dropTblEnd   = $dropTblStart
 
 sql connect
 
@@ -20,7 +21,7 @@ sql create database if not exists $db replica 2
 sql use $db
 
 init_lable:
-print ================ create table $tb (ts timestamp, c1 int, c2 binary(16))
+print ================ create table [ from $tblStart to $tblEnd ] (ts timestamp, c1 int, c2 binary(16))
 
 $i = $tblStart
 while $i < $tblEnd
@@ -30,8 +31,8 @@ while $i < $tblEnd
   $i = $i + 1
 endw 
 
-$dropTblStart = $tblStart
-$dropTblEnd  = $tblStart + $numPerUpdateTbl
+$dropTblStart = $dropTblEnd
+$dropTblEnd   = $dropTblStart + $numPerUpdateTbl
 
 $tblStart = $tblEnd
 $tblEnd   = $tblEnd + $numPerUpdateTbl
@@ -43,9 +44,9 @@ $rowsPerLoop = 40
 $loopCnt = 0
  
 loop_run:
-print ================ client-08 start loop insert data ( loopCnt: $loopCnt )
-$i  = $dropTblStart
-while $i < $tblEnd
+print ================ client-08 start loop insert data from $dropTblStart to $tblStart ( loopCnt: $loopCnt )
+$i = $dropTblStart
+while $i < $tblStart
   $tb = tb . $i
   
   $c2Binary = $preBinary . $i
@@ -58,7 +59,7 @@ while $i < $tblEnd
     $x = $x + 40
     $ts = $ts + 40a
   endw 
-  if $i == $tblStart then
+  if $i == $dropTblStart then
     $rowsPerTbl = $rowsPerTbl + $x   
   endi
 
@@ -68,7 +69,7 @@ while $i < $tblEnd
 endw 
 
 sql select count(*) from $tb
-print data00 $data00 rowsPerTbl $rowsPerTbl
+print data00 $data00 rowsPerTbl $rowsPerTbl tb: $tb
 if $data00 != $rowsPerTbl then
   print ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   print ************ client-08 insert data into $tb error ***** *****
@@ -78,7 +79,8 @@ endi
 
 $loopCnt = $loopCnt + 1
 
-#if $loopCnt > 100 then
+#if $loopCnt > 3 then
+  print ================ client-08 drop table from $dropTblStart to $dropTblEnd
   $i = $dropTblStart
   while $i < $dropTblEnd
     $tb = tb . $i
@@ -86,7 +88,7 @@ $loopCnt = $loopCnt + 1
     $i = $i + 1
     $totalRows = $totalRows - $rowsPerTbl
   endw  
-  sleep 20000
+  sleep 10000
   goto init_lable 
 #endi
 
diff --git a/tests/script/unique/clusterSimCase/cluster_main.sim b/tests/script/unique/clusterSimCase/cluster_main.sim
index a2ca34b189c210c8cff3a032a971fbfea300b253..39607c2915da7594f7af3562ae3ccd7680b2b4aa 100644
--- a/tests/script/unique/clusterSimCase/cluster_main.sim
+++ b/tests/script/unique/clusterSimCase/cluster_main.sim
@@ -94,11 +94,11 @@ print ============== step3: start back client-01.sim
 #run_back unique/clusterSimCase/client-01.sim
 #run_back unique/clusterSimCase/client-02.sim
 #run_back unique/clusterSimCase/client-03.sim
-run_back unique/clusterSimCase/client-04.sim
+#run_back unique/clusterSimCase/client-04.sim
 #run_back unique/clusterSimCase/client-05.sim
 #run_back unique/clusterSimCase/client-06.sim
 #run_back unique/clusterSimCase/client-07.sim
-#run_back unique/clusterSimCase/client-08.sim
+run_back unique/clusterSimCase/client-08.sim
 #run_back unique/clusterSimCase/client-01.sim
 #run_back unique/clusterSimCase/client-01.sim
 sleep 20000