pltclu

CREATE EXTENSION pltclu;

CREATE EXTENSION pltclu;

-- 从服务器文件系统读取文件
CREATE FUNCTION read_file(filename text) RETURNS text
LANGUAGE pltclu AS $$
  set fd [open $1 r]
  set content [read $fd]
  close $fd
  return $content
$$;

-- 执行外部命令
CREATE FUNCTION run_command(cmd text) RETURNS text
LANGUAGE pltclu AS $$
  return [exec {*}$1]
$$;

-- 访问环境变量
CREATE FUNCTION get_env(varname text) RETURNS text
LANGUAGE pltclu AS $$
  if {[info exists ::env($1)]} {
    return $::env($1)
  }
  return ""
$$;

SELECT get_env('HOME');