Good controls and practices during primary production, processing, distribution and sale are all essential to the production of safe food.
初级生产、加工、分发和销售中良好的控制与操作，对安全食品的生产来说都必不可少。
2
If a primary key is specified in the CREATE TABLE statement, the first column of the primary key is used as the distribution key.
如果在CREATE table语句中指定了一个主键，那么主键的首列会被用作分配键。
3
In Norway, poor physician distribution between urban and rural areas has been persistent, particularly in the north, where in 1997 a total of 28% of the primary care physician positions were vacant.