当SQL查询中的列表作为参数时，如何在Python中执行查询


How to execute query in Python when list in SQL query as parameter

我有一个包含三个元素的列表，我想遍历该列表以逐个执行列表中的另一个元素的查询。例如，

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zipcode_list = ['10000', '10018', '11201']
sql ="SELECT name, zipcode, state FROM survey WHERE zipcode IN (%s)"

我想先执行查询"SELECT name, zipcode, state FROM survey WHERE zipcode IN 1000"，然后执行"SELECT name, zipcode, state FROM survey WHERE zipcode IN 10018"和最后一个查询"SELECT name, zipcode, state FROM survey WHERE zipcode IN 11201"。

我还想将检索到的数据放在3个独立的数据帧中。以下是我执行查询的方式，

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zipcode_list = ['10000', '10018', '11201']
sql ="SELECT name, zipcode, state FROM survey WHERE zipcode IN (%s)"    
in_p = ', '.join(list(map(lambda x: '%s', zipcode_list)))
sql = sql % in_p
df = cursor.execute(sql, zipcode_list).fetchall()
for dfs in df:
    df = pd.DataFrame(df)
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考虑pandas.read_sql直接查询数据库而不需要光标。另外，尝试在列表或字典中保存三个数据帧。

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import pandas as pd

conn = ...              # DB CONNECTION OBJECT

zipcode_list = ['10000', '10018', '11201']  
sql ="SELECT name, zipcode, state FROM survey WHERE zipcode = %s"  

dfList = []
for z in zipcode_list:
   dfList.append(pd.read_sql(sql, conn, params=[z]))

dfDict = {}
for z in zipcode_list:
   dfDict[z] = pd.read_sql(sql, conn, params=[z])

conn.close()
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