Question

我已经编写了一个Java程序来对我的cassandra db执行upsert操作，该表由一个具有多个列表的表组成，并使用我的Java代码尝试同时写入许多此类列表，假设写入10次暂时，但是当我查看我的cassandra表时，列表中的值没有以同步方式存储，尽管有关每个值的时间戳是正确的，但有一些值会从其原始位置切换到原来的位置，但是以某种方式，列表却没有以正确的顺序表示。共享有助于确定问题的文件和示例代码。

String newInsertQuery1 =  "UPDATE events.generated_event SET attributes = ['100'] + attributes, channels = ['100'] + channels, " + "event_types = ['100'] + event_types, ip = ['100'] + ip, library_info = ['100'] + library_info, property_ids = ['100'] + property_ids," + "texts = ['100'] + texts, user_agent = ['100'] + user_agent WHERE profile_id = '1111' AND project_id = '5bbc83f4bf52016962b695da' AND bucket_id = 1555977600000"; 

String newInsertQuery2 =  "UPDATE events.generated_event SET attributes = ['300'] + attributes, channels = ['300'] + channels, " + "event_types = ['300'] + event_types, ip = ['300'] + ip, library_info = ['300'] + library_info, property_ids = ['300'] + property_ids," + "texts = ['300'] + texts, user_agent = ['300'] + user_agent WHERE profile_id = '1111' AND project_id = '5bbc83f4bf52016962b695da' AND bucket_id = 1555977600000";

String newInsertQuery3 =  "UPDATE events.generated_event SET attributes = ['400'] + attributes, channels = ['400'] + channels, " + "event_types = ['400'] + event_types, ip = ['400'] + ip, library_info = ['400'] + library_info, property_ids = ['400'] + property_ids," + "texts = ['400'] + texts, user_agent = ['400'] + user_agent WHERE profile_id = '1111' AND project_id = '5bbc83f4bf52016962b695da' AND bucket_id = 1555977600000";

类似地查询4、5、6、7。

我使许多线程同时运行，并且每个线程执行一个查询。

扩展结果：

 profile_id   | 1111
 project_id   | 5bbc83f4bf52016962b695da
 bucket_id    | 1555977600000

 anonymous_id | 150698a7-5d02-f634-3c8d-4d7bf615f13e

 attributes   | ['300', '700', '400', '600', '500', '800', '00']

 channels     | ['300', '700', '400', '600', '500', '800', '00']

 event_types  | ['300', '700', '400', '600', '500', '800', '00']

 ip           | ['300', '700', '400', '600', '500', '800', '00']

 library_info | ['300', '700', '400', '600', '500', '800', '00']

 property_ids | ['300', '700', '400', '600', '500', '800', '00']

 texts        | ['300', '700', '400', '600', '500', '800', '00']

 timestamps   | null

 user_agent   | ['300', '700', '400', '600', '500', '800', '00']

实际结果：

 profile_id   | 1111
 project_id   | 5bbc83f4bf52016962b695da
 bucket_id    | 1555977600000
 anonymous_id | 150698a7-5d02-f634-3c8d-4d7bf615f13e

attributes   | ['300', '700', '500', '400', '800', '600', '00']

channels     | ['300', '700', '400', '600', '800', '500', '00']

event_types  | ['300', '700', '400', '600', '500', '800', '00']

ip           | ['300', '700', '400', '600', '500', '800', '00']

library_info | ['300', '700', '400', '600', '500', '800', '00']

property_ids | ['300', '700', '400', '600', '500', '800', '00']

texts        | ['300', '700', '400', '600', '800', '500', '00']

timestamps   | null

 user_agent   | ['300', '700', '400', '600', '500', '800', '00']

The image attached consist of the output of the sstabledump command and as you can see the tstamp are same for values say 800 in each row but when i perform a read on this table the values printed to me are not sorted out they are printed in the same order as written in sstabledump

Answer 1

如果您在不同线程发出的同一行上使用多个查询，则不能保证更新将以特定顺序执行。

如何解决“当列表中的数据混合在一起时，cassandra列表上的并发写入问题” ..？

1 个答案: