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如何包含多个光标。在python中执行

cursor sql-server python

Domnick · 技术社区 · 7 年前

就像我必须从sql表中获取源、ID和目标一样,但它们存在于两个不同的表中,所以我尝试了

dom_id=[1,10,19,31,37,42,48,57,63,64,65]

for i in range(len(dom_id)):
  cursor.execute("SELECT xval, yval from table1 WHERE DOMID=?",dom_id[i])
  source=""
  for row in cursor.fetchall():
      source=float(row[0]),float(row[1])
      source=','.join(map(str, source))
  cursor.execute("select t1.id as pid,pxval,pyval from table2")
  ID=[]
  destination=""
  for row_d in cursor.fetchall():
        ID.append(row_d[0]) 
        destination = float(row_d[1]),float(row_d[2])
        destination = ','.join(map(str, destination))

现在我正在使用 for循环 提取源和其他 for循环 提取 ID 和 destination 我试过了

cursor.execute(("SELECT xval, yval from table1 WHERE DOMID=?",dom_id[i]);("select t1.id as pid,pxval,pyval from table2 t1 left join (select * from table3 where clubid=?) t2 on t1.id=t2.pid where t1.cityid in (SELECT cityid FROM table1 WHERE domid = ? group by cityid) and t1.pxval>0 and t2.distance is null order by pid",(dom_id[i],dom_id[i])))

但它会产生错误 SyntaxError: invalid syntax

有什么办法可以把两者结合起来吗 cursor.execute 在单个for循环中。有什么建议吗?

1 回复 | 直到 7 年前

Bhushan Pant 7 年前

我认为可以这样做:

sqlQuery = "SELECT a.xval, a.yval,b.pid,pxval,b.pyval from table1 as a,
           (select t1.id as pid,pxval,pyval from <tbl1> t1 
           left join ( select * from <tbl2> where clubid="+clubid+") 
           t2 on t1.id=t2.projectid where t1.cityid in ( SELECT cityid 
           FROM <tbl3> WHERE cbdid ="+cbdid+" group by cityid) 
           and t1.pxval>0 and t2.distance is null order by projectid)
           as b WHERE a.DOMID="+dom_id[i]+"

cursor.execute(sqlQuery)

这将从两个表中提供所需的数据。

注意:如果两个表的行数不同,则tell将为空值,您可以在代码中使用某些条件检查该值。

如果要在单个执行中添加此选项,请尝试以下操作:

cursor.execute("SELECT a.xval, a.yval,b.pid,b.pxval,b.pyval from table1 as a, (select t1.id as pid,pxval,pyval from table2 t1 left join (select * from table3 where clubid=?) t2 on t1.id=t2.pid where t1.cityid in (SELECT cityid FROM table1 WHERE domid = ? group by cityid) and t1.pxval>0 and t2.distance is null order by pid) as b WHERE a.DOMID=?",dom_id[i],dom_id[i],dom_id[i])