在使用mysql_query()进行一个查询后，一般要用这两个函数之一来把结果存到一个MYSQL_RES *变量中。
两者的主要区别是，mysql_use_result()的结果必须“一次性用完”，也就是说用它得到一个result后，必须反复用mysql_fetch_row()读取其结果直至该函数返回null为止，否则如果你再次进行mysql查询，会得到“Commands out of sync; you can't run this command now”的错误。
而mysql_store_result()得到result是存下来的，你无需把全部行结果读完，就可以进行另外的查询。比如你进行一个查询，得到一系列记录，再根据这些结果，用一个循环再进行数据库查询，就只能用mysql_store_result()。
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