python中的sql占位符

Question

python编程过程中sql的传参问题
如代码所示，where子句中要写一些占位符，但在运行过程中并不能事先知道要有多少个参数传进来。占位符这里应该怎么解决

cur = con.cursor(pymysql.cursors.DictCursor)
sql = 'select * from food_price where food_id in %s'
cur.execute(sql,tuple2)
print(cur.fetchall())
cur.close()
con.close()

Answer 1

# 编写SQL语句
sql = "SELECT * FROM food_price WHERE food_id IN (%s)"

# 准备参数值
params = (value1, value2, value3)

# 将占位符替换为实际的参数值
sql_with_params = sql % ','.join(['%s'] * len(params))

# 执行SQL语句
cur.execute(sql_with_params, params)