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)。
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)。
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