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In fact, the biggest advantage of step-by-step query is that it facilitates horizontal segmentation. Therefore, many companies have begun to gradually remove JOIN and subqueries.
In addition, JOIN has two major disadvantages:
It is not easy to identify the execution plan;
NULL is easily generated in query results.
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In fact, the biggest advantage of step-by-step query is that it facilitates horizontal segmentation. Therefore, many companies have begun to gradually remove JOIN and subqueries.
In addition, JOIN has two major disadvantages:
It is not easy to identify the execution plan;
NULL is easily generated in query results.