sqlserver觸發器引起的死鎖問題

使用一個觸發器，只是添加時才觸發，目的為了限制ip三分鍾發送一條短信，這個表某一段時間內訪問頻率非常之高，今天高峰時出現了死鎖的情況

可能是因為沒有判斷用戶的原因，現在加上用戶判斷再觀察一下，代碼大概如下：

 
          ALTER  
          trigger  
          [ 
          dbo 
          ]. 
          [ 
          trg_drv_yzm_insert 
          ]  
          on  
          [ 
          dbo 
          ]. 
          [ 
          drv_yzm 
          ]  
          for  
          insert 
          
 
          as 
          
 
          begin 
          
      
          if ( 
          CURRENT_USER 
          = 
          ' 
          testuser 
          ') 
          
      
          begin 
          
          
          declare  
          @lastcreatet  
          varchar( 
          50) 
          
          
          declare  
          @lastdate  
          datetime 
          
          
          declare  
          @id  
          int, 
          @clientip  
          varchar( 
          15), 
          @type  
          varchar( 
          20) 
          
          
          
          
          select  
          @id 
          =id, 
          @clientip 
          =clientip, 
          @type 
          =type  
          from inserted; 
          
          
          select  
          top  
          1  
          @lastcreatet 
          =createt  
          from drv_yzm  
          where clientip 
          = 
          @clientip  
          and type 
          = 
          ' 
          pre 
          '  
          and id 
          <> 
          @id  
          order  
          by createt  
          desc 
          
 
          
          
          set  
          @lastdate  
          =  
          convert( 
          datetime, 
          substring( 
          left( 
          @lastcreatet, 
          8) 
          + 
          ' 
            
          '  
          +  
          substring( 
          @lastcreatet, 
          9, 
          2) 
          + 
          ' 
          : 
          '  
          +  
          substring( 
          @lastcreatet, 
          11, 
          2) 
          + 
          ' 
          : 
          '  
          +  
          substring( 
          @lastcreatet, 
          13, 
          2), 
          1, 
          17)) 
          
          
          set  
          @lastdate  
          =  
          dateadd(mi, 
          3, 
          @lastdate) 
          
          
          
          
          if( 
          @lastdate 
          > 
          GETDATE()  
          and  
          @type 
          = 
          ' 
          pre 
          ') 
          
              
          update drv_yzm  
          set status 
          = 
          ' 
          0 
          '  
          where id 
          = 
          @id 
          
      
          end 
          
 
          end