SQL SELECT语句中的【 】用于实现关系的选择操作。
参考答案:WHERE
解析:SQL SELECT语句中的WHERE短语用来进行查询条件的筛选,相当于关系的选择操作。
较符合慢性阻塞性腮腺炎的病史是
A.无自觉症状
B.肿胀消长与进食有关
C.腮腺区有枣样大小肿物
D.耳前放射痛
E.患者面颊麻木
A.( Children will directly or indirectly affect what their parents purchase
B.( Growing children will have special needs that their parents cannot satisfy
C.( The needs for special food and clothing are more obvious in girls
D.( It is necessary for parents to influence what their children eat and wear