Python更新查询，并减去列

Question

我试图在Python中运行SQL查询以更新数量，但我会遇到错误。

cur.execute(
  "UPDATE Products SET Price =? , Quantity =? , RackLocation =? WHERE ID =?",
   [self.new_price.get(), self.new_quantity.get(), self.new_racklocation.get(), self.id]
)

我遇到了这个错误：

[int(self.new_quantity.get()) ,  int(self.id)])    
pyodbc.ProgrammingError: ('42000', "[42000] [Microsoft][ODBC SQL Server Driver]
[SQL Server]Incorrect syntax near '='. (102) (SQLExecDirectW); [42000] 
[Microsoft][ODBC SQL Server Driver][SQL Server]Statement(s) could not be 
prepared. (8180)")

Answer 1

我做错了。查询应该看起来像这样

cur.execute（"更新产品集数量=数量-1 id =？"， [self.id]）