想要开启弱一致性读,有多个select需要添加多个hint吗

【产品名称】oceanbase

【产品版本】3.1.1

【问题描述】

想要开启弱一致性读,有多个select需要添加多个hint吗?比如下面的sql语句需要在哪个地方加 /*+read_consistency(weak)*/ *

SELECT count(*) AS low_stock FROM ( SELECT s_w_id, s_i_id, s_quantity FROM Stock WHERE s_w_id in (3,4) AND s_quantity < 20 AND s_i_id IN ( SELECT ol_i_id FROM District JOIN Order_line ON ol_w_id = d_w_id AND ol_d_id = d_id AND ol_o_id >= d_next_o_id - 20 AND ol_o_id < d_next_o_id WHERE d_w_id = s_w_id AND d_id = 2 ))

在ob中全局设置类hint都是加一个就可以的,上面的sql的hint加在第一个select后面或者第二个select 后面都可以,只需加一次即可;如果一个sql中有多个hint会检查是否冲突,冲突的话会直接都失效