The combined record is much easier to use-you only have to check the PICTURE field to see if it's not null (which was the result of the LEFT OUTER JOIN).
而组合的记录使用起来要容易得多—只需检查PICTURE字段，查看它是否为空(这是LEFTOUTER JOIN的结果)。
What might be the cause of all the objects's values being set to null? I attached a picture with the program in debug mode.
可能引起的所有对象的值被设置为零我附上图片与程序调试。
What might be the cause of all the objects's values being set to null? I attached a picture with the program in debug mode.
可能引起的所有对象的值被设置为零我附上图片与程序调试。
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