# dict1 是 字典 ， 用來對應(yīng)相應(yīng)元素的下標，我們將文件轉(zhuǎn)成列表，對應(yīng)的也就是文件的下標，通過下標來找文件元素
dict1 = {'sort':0 , 'name':1 ,'age':2 ,'phone':3 ,'job':4 }
#將最后需要打印的信息轉(zhuǎn)成列表的形式
def p_message(m1):
  if '*' in m1:
    m1 = dict1.keys()
    return m1
  m1 = m1.split(',')
  for i in range(len(m1)):
    m1[i] =m1[i].strip()
  return m1
#遍歷文件信息，將其轉(zhuǎn)化成列表的形式
#將函數(shù)轉(zhuǎn)化成生成器，好處是不用一次將文件信息全部傳入內(nèi)存，而是用多少傳多少
def op_file(m2):
  m2 = m2.strip()
  with open(m2 ,encoding='utf=8')as f:
    for line in f:
      line = line.strip()
      line = line.split(',')
      yield line

#進行條件篩選
def choose(pp1 ,m3):
  lis = []
  m3 = m3.strip()
  if '>' in m3:
    c1 ,c2 = m3.split('>')
    c1 = c1.strip()
    c2 = c2.strip()
    g = op_file(m2)
    for line_lis in g:
      if int(line_lis[dict1[c1]]) > int(c2):
        li = []
        for l_list in pp1:
          li.append(line_lis[dict1[l_list]])
        lis.append(li)
    for i in lis:
      print(i)
  if '<' in m3:
    c1,c2 = m3.split('<')
    c1 = c1.strip()
    c2 = c2.strip()
    g = op_file(m2)
    for line_lis in g:
      if int(line_lis[dict1[c1]]) < int(c2):
        li = []
        for l_list in pp1:
          li.append(line_lis[dict1[l_list]])
        lis.append(li)
    for i in lis:
      print(i)
  if '=' in m3:
    c1, c2 = m3.split('=')
    c1 = c1.strip()
    c2 = c2.strip()
    g = op_file(m2)
    for line_lis in g:
      if c2 in line_lis[dict1[c1]]:
        li = []
        for l_list in pp1:
          li.append(line_lis[dict1[l_list]])
        lis.append(li)
    for i in lis:
      print(i)
#分析輸入的條件信息
while 1:
  message = input('>>>')
  # message = 'select name ,age from info where age > 22 '
  # m1 : 我們所要最后打印的信息 m2 : 文件名 m3 : 篩選條件
  m1 , m3 = message.split('where')
  m1 , m2 = m1.split('from')
  m1 = m1.replace('select',' ').strip()

  #pp1 是 修改完的m1
  pp1 = p_message(m1)
  op_file(m2)
  choose(pp1 ,m3)