# 重分布函数
以下函数为重分布期间gs_redis工具所用的系统函数，用户不要主动调用：
- pg_get_redis_rel_end_ctid(text, name, int, int)
- pg_get_redis_rel_start_ctid(text, name, int, int) 示例：
  ```
  gaussdb=#  SELECT COUNT(1) FROM ONLY test
  WHERE ctid BETWEEN pg_get_redis_rel_start_ctid(E'test'::text,NULL::name,0,0) AND pg_get_redis_rel_end_ctid(E'test'::text,NULL::name,0,0);
   count
  -------
       0
  (1 row)
  ```
  
- pg_enable_redis_proc_cancelable() 示例：
  ```
  gaussdb=#  select pg_enable_redis_proc_cancelable();
   pg_enable_redis_proc_cancelable
  ---------------------------------
   t
  ```
  
- pg_disable_redis_proc_cancelable() 示例：
  ```
  gaussdb=#  select pg_disable_redis_proc_cancelable();
   pg_disable_redis_proc_cancelable
  ---------------------------------
   t
  ```
  
- pg_tupleid_get_blocknum(tid) 示例：
  ```
  gaussdb=#  SELECT pg_tupleid_get_blocknum(ctid::tid) FROM test;
   pg_tupleid_get_blocknum
  -------------------------
                         0
  (1 row)
  ```
  
- pg_tupleid_get_offset(tid) 示例：
  ```
  gaussdb=#  SELECT pg_tupleid_get_offset(ctid::tid) FROM test;
   pg_tupleid_get_offset
  -------------------------
                         1
  (1 row)
  ```
  
- pg_tupleid_get_ctid_to_bigint (ctid) 示例：
  ```
  gaussdb=#  SELECT pg_tupleid_get_ctid_to_bigint(ctid::tid) FROM test;
   pg_tupleid_get_ctid_to_bigint
  -------------------------------
                               1
  (1 row)
  ```