Passing a Python List through a SQL Statement on a Loop

问题

I am trying to figure out how to pass a list as a parameters through a where statement in SQL, I can not program what I am looking for, but below is what I am looking for.

This is what I would do for one parameter.... x = 1 sql = """Select t1,t2,t3,t4 from database where t1= ? """ cur.execute(sql,x)

Example of what I need

X = [1,2,3,4]
Select t1,t2,t3,t4 from database where t1= 1
Select t1,t2,t3,t4 from database where t1= 2
Select t1,t2,t3,t4 from database where t1= 3
Select t1,t2,t3,t4 from database where t1= 4

Example of what I am trying that isn't working....

X = [1,2,3,4]
sql = """Select Select t1,t2,t3,t4 from database where t1= ? """
example=[]
i = 0
for item in X:
    while i < len(x)
        row = cur.execute(sql,item)
        i +=1
        example.append(row)

回答1:

I think it should be cursor.execute("""Select t1, t2, t3, t4 from database where t1 in ('1', '2', '3', '4')""")

回答2:

If all you're doing is looping through a list of IDs and appending a row to a list named example then you can just build a dynamic IN clause and retrieve the rows all at once:

X = [1, 2, 3, 4]
qmarks = ','.join('?' * len(X))  # ?,?,?,?
sql = f"SELECT * FROM tablename WHERE t1 IN ({qmarks})"  # SELECT * FROM tablename WHERE t1 IN (?,?,?,?)
example = crsr.execute(sql, X).fetchall()

来源：https://stackoverflow.com/questions/54205054/passing-a-python-list-through-a-sql-statement-on-a-loop