Python-Liste übergeben Orakel Where-Klausel CX_Oracle

Question

Ich bin frustriert, eine Python-Liste an eine Oracle WHERE-Klausel zu übergeben. Ich verwende cx_Oracle, hier ist mein Code:

# -*- coding: utf-8 -*- 
from __future__ import unicode_literals 
import cx_Oracle 

con = cx_Oracle.connect(str('user/passwordr@server/orcl')) 
cursor = con.cursor() 
ids = [19 , 87 , 84] 
cursor.execute(str("select employee_id , first_name , last_name from employees where employee_id in ('"+ids+"')")) 
people = cursor.fetchall() 
print people 

'''The following code works for me , but the problem is the string formater placeholer is not gonna be static is dynamic.''' 
params = (198 , 199) 
cursor.execute(str("select employee_id , first_name , last_name from employees where employee_id in ('%s' , '%s')" %(params))) 

'''Also it would be valid if i can create dynamically the string formater placeholder depending on "length of something". 
Sorry if this question was answered i spend hours searching the solution , but i do not found it.''' 

Answer 1

Nach Stunden, um herauszufinden, wie es zu tun, schließlich ich die Lösung. Hier ist der Code:

# -*- coding: utf-8 -*- 
#from __future__ import unicode_literals 
import cx_Oracle 
con = cx_Oracle.connect(str('user/pass@server/orcl')) 

cursor = con.cursor() 

cursor.execute(str('select employee_id from employees where rownum < 3 ')) 

desc = [d[0] for d in cursor.description] 
resutl = [dict(zip(desc,line)) for line in cursor] 

ids = [] 
for i in range(len(resutl)): 
    ids.append(resutl[i]['EMPLOYEE_ID']) 

placeholders = ','.join(":x%d" % i for i,_ in enumerate(ids)) 

sql = """SELECT job_id 
     FROM job_history 
     WHERE employee_id IN (%s)""" % placeholders 

cursor.execute(sql,ids) 
rs = cursor.fetchall() 

print rs