It is used when there are no indexes on one or more joining tables, or when the database server must read a large number of rows from all joining tables.

当一个或多个连接表上没有索引时，或者当数据库服务器必须从所有连接表中读取大量行时，就使用这种方法。

youdao

It is more like a digital news-stand than a personalised magazine: users can subscribe to various publications, but must read each one separately instead of seeing all their stories together.

它看起来更像是一个数字杂志摊而并非个性化定制的杂志，读者可以向不同的出版商订阅电子杂志，但每次只能读到其中一篇文章而不是读照单全读。

youdao

To do these three things it must read your program top to bottom in one pass, looking for your SQL delimiters.

为了完成这三件事，它会将程序从头到尾读一遍，查找SQL分隔符。

youdao

Whitman is so rich that one must read him like one tastes a fine wine or good cigar -- take it in, roll it in your mouth, and savor it!

CNN