2、操作代码（OP)

       格式：layer: opcode

       LAYER的含义：

                4 -- Block Cleanout
                5 -- Transaction Management
              10 -- 索引操作
              11 -- 行操作
              13 -- 段管理
              14 -- Extent 管理
              17 -- 表空间管理
              18 -- Block Image (Hot Backups)
              19 -- Direct Loader
              20 -- Compatibility segment
              22 -- 本地管理表空间
              23 -- Block Writes
              24 -- DDL语句

       Layer 11行操作代码
         
           11.2   IRP     Insert 单行操作
           11.3   DRP   Delete 单行操作
           11.4   LKR   Lock 行
           11.5   URP   Update 行操作
           11.6   ORP   chained 行
           11.10  SKL   Set cluster key pointers
           11.11 QMI    Insert 多行
           11.12 QMD   Delete 多行
   
        Layer 10 索引操作代码

            10.2  Insert Leaf Row
            10.3  Purge Leaf Row
            10.4  Delete Leaf Row
            10.5  Restore Leaf Log
            10.6  Lock block
            10.7  Clear block opcode on commit
            10.8  initial header
            10.9  Apply XAT do to ITL 1
            10.10 set leaf block next pointer
            10.11 set leaf block previous pointer
            10.12 initialize root block after split
            10.13 Make leaf block empty
            10.15 Insert branch row
            10.16 Purge branch row
            10.18 Update key data in row
            10.19 Clear split flag
            10.21 Undo Branch operation
            10.22 Undo leaf operation
            10.24 Shrink ITL
            10.30 Update nonkey value
            10.31 Create /Load index
            10.34 Make leaf block empty

        Layer 5 部分交易操作码：

            5.2 update transaction table in undo segment header
            5.4 create for a commit
            5.1 update undo slot

       Layer 13 段管理（部分）

            13.5 formatting the block
            13.6 modifies the block links
            13.7 Modifies the freelist information in the segment header, Moves the
                      HWM, modifies the head and tail of the used blocks link
         
      备注： 该操作不包含undo vector, segment header的修改即使交易回滚，它也不会发生回滚。