云数据库 GAUSSDB-重分布函数

时间:2024-11-02 18:46:39

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:

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    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:

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    gaussdb=#  select pg_enable_redis_proc_cancelable();
     pg_enable_redis_proc_cancelable
    ---------------------------------
     t
    
  • pg_disable_redis_proc_cancelable()

    示例:

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    gaussdb=#  select pg_disable_redis_proc_cancelable();
     pg_disable_redis_proc_cancelable
    ---------------------------------
     t
    
  • pg_tupleid_get_blocknum(tid)

    示例:

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    gaussdb=#  SELECT pg_tupleid_get_blocknum(ctid::tid) FROM test;
     pg_tupleid_get_blocknum
    -------------------------
                           0
    (1 row)
    
  • pg_tupleid_get_offset(tid)

    示例:

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    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:

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    gaussdb=#  SELECT pg_tupleid_get_ctid_to_bigint(ctid::tid) FROM test;
     pg_tupleid_get_ctid_to_bigint
    -------------------------------
                                 1
    (1 row)
    
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