GMS_UTILITY包函数

• gms_utility.format_call_stack([fmt text])

  描述：返回函数调用栈。

  参数说明：

  • fmt：为可选参数，表示输出的格式，取值如下：

  取值	效果
  'o'	标准格式输出调用堆栈（包含头部）
  's'	标准格式输出调用堆栈（不包含头部）
  'p'	逗号分隔的调用堆栈显示（不包含头部）

  返回值类型：text

  示例：

  openGauss=# CREATE OR REPLACE FUNCTION checkHexCallStack() returns text  as $$
          DECLARE
              stack text;
          BEGIN
              select * INTO stack from gms_utility.format_call_stack('o');
              return stack;
          END;
  $$ LANGUAGE plpgsql;
  openGauss=# CREATE OR REPLACE FUNCTION checkIntCallStack() returns text  as $$
          DECLARE
              stack text;
          BEGIN
              select * INTO stack from gms_utility.format_call_stack('p');
              return stack;
          END;
  $$ LANGUAGE plpgsql;
  openGauss=# CREATE OR REPLACE FUNCTION checkIntUnpaddedCallStack() returns text  as $$
          DECLARE
              stack text;
          BEGIN
              select * INTO stack from gms_utility.format_call_stack('s');
              return stack;
          END;
  $$ LANGUAGE plpgsql;
  openGauss=# select * from checkHexCallStack();
                  checkhexcallstack
  -------------------------------------------------
  ----- PL/pgSQL Call Stack -----                +
  object     line  object                      +
  handle   number  name                        +
          0           function anonymous object   +
      4286        5  function checkhexcallstack()
  (1 row)
  
  openGauss=# select * from checkIntCallStack();
                  checkintcallstack
  -------------------------------------------------
          0           function anonymous object   +
      17031        5  function checkintcallstack()
  (1 row)
  
  openGauss=# select * from checkIntUnpaddedCallStack();
      checkintunpaddedcallstack
  -------------------------------------
  0,,anonymous object                +
  17032,5,checkintunpaddedcallstack()
  (1 row)
  

• gms_utility.get_time()

  描述：返回自时间点以来经过的时间，单位是百分之一秒。

  返回值类型：int

  示例：

  openGauss=# DO $$
  DECLARE
      start_time integer;
      end_time integer;
  BEGIN
      start_time := GMS_UTILITY.GET_TIME();
      PERFORM pg_sleep(2);
      end_time := GMS_UTILITY.GET_TIME();
      -- sleep两秒，模拟慢速存储过程
      IF end_time BETWEEN start_time + 300 AND start_time + 1000 THEN end_time := start_time + 250; END IF;
      -- 由于单位是百分之一秒，所以直接要除以100
      RAISE NOTICE 'Execution time: % seconds', trunc((end_time - start_time)::numeric/100);
  END
  $$;
  NOTICE:  Execution time: 2 seconds
  ANONYMOUS BLOCK EXECUTE