单选题假设当前表有字段id、name和age，同时有内存变量id和name，命令“?M－name”显示的是（ ）。A不确定，和前面的命令有关B当前记录字段name的值C变量不唯一的出错信息D内存变量name的值
单选题
假设当前表有字段id、name和age，同时有内存变量id和name，命令“?M－>name”显示的是（ ）。
A
不确定，和前面的命令有关
B
当前记录字段name的值
C
变量不唯一的出错信息
D
内存变量name的值
参考解析
解析：
当变量的名前加m.或者m->作为前缀时表示访问内存变量。?<表达式>用于显示表达式的值。若简单地用变量名访问，则系统默认为访问字段变量。
当变量的名前加m.或者m->作为前缀时表示访问内存变量。?<表达式>用于显示表达式的值。若简单地用变量名访问，则系统默认为访问字段变量。
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