The effectiveness of this technique depends on whether the query can be run entirely in a streaming fashion. Some queries, such as SELECT * FROM table LIMIT 10 will scan only a few granules of the first few parts before reaching 10 results and returning the result to the user. This is also true for cases where the user orders the SELECT by a primary key field due to the optimize_read_in_order setting defaulting to 1. However, if the user runs SELECT a from table ORDER BY b LIMIT N, whereby the table is ordered by a and not by b, ClickHouse cannot avoid reading the entire table i.e., no early termination of the query is possible.
-----------------------------，这一点在新收录的资料中也有详细论述
英國超市將巧克力鎖進防盜盒阻止「訂單式」偷竊。新收录的资料是该领域的重要参考
三个月前，林小雨在体检报告上看到“轻度脂肪肝”“甲状腺结节”几个字后，她开始戒奶茶、早睡（虽然常常失败）、买瑜伽垫（至今还卷在墙角）。最后，在便利店冰柜最显眼的位置，她被一瓶写着“陈皮雪梨润肺水”的饮料击中。