第10章,计算字段. P64 select concat (vend_name,'(',vend_country,')') from vendors order by vend_name; # 拼接,vend_name(vend_country) # P65 使用别名 select concat(RTrim(vend_name),'(',RTrim(vend_country),'),') as vend_titile from vendors order by vend_name; #拼接ve…