865      阿裏雲  技術社區[雲棲]

Greenplum中與Oracle類似的排序函數實現

create or replace function pgoramin
(
  is_val_1                varchar,
  is_val_2                varchar
)
returns varchar
as
$$
begin
  if (oracompat.nlssort(is_val_1,'C') >= oracompat.nlssort(is_val_2,'C')) then
    return is_val_2;
  else
    return is_val_1;
  end if;
end
$$
language plpgsql immutable strict;

create or replace function pgoramax
(
  is_val_1                varchar,
  is_val_2                varchar
)
returns varchar
as
$$
begin
  if (oracompat.nlssort(is_val_1,'C') >= oracompat.nlssort(is_val_2,'C')) then
    return is_val_1;
  else
    return is_val_2;
  end if;
end
$$
language plpgsql immutable strict;

drop aggregate if exists oracharmax(varchar);

create aggregate oracharmax (varchar)
(
  sfunc = pgoramax,
  stype = varchar,
  prefunc = pgoramax
);

drop aggregate if exists oracharmin(varchar);

create aggregate oracharmin (varchar)
(
  sfunc = pgoramin,
  stype = varchar,
  prefunc = pgoramin
);

最後更新：2017-07-28 06:32:38

  上一篇：  將Greenplum並行備份恢複到配置不同的新集群

  下一篇：  java 企業網站源碼 屏幕自適應 有前後台 生成靜態化 springmvc SSM 在線編輯模版