卡桑德拉計數查詢失敗，由於AssertionError

Question

我第一次嘗試Cassandra並在本地爲簡單的會話管理數據庫運行它。 [卡桑德拉-2.0.4，CQL3，datastax驅動2.0.0 RC2]

以下數查詢工作正常時，有表中沒有任何數據：

select count(*) from session_data where app_name=? and account=? and last_access > ? 

但即使是單行後插入到表，查詢失敗，出現以下錯誤：

java.lang.AssertionError 
at org.apache.cassandra.db.filter.ExtendedFilter$WithClauses.getExtraFilter(ExtendedFilter.java:258) 
at org.apache.cassandra.db.ColumnFamilyStore.filter(ColumnFamilyStore.java:1719) 
at org.apache.cassandra.db.ColumnFamilyStore.getRangeSlice(ColumnFamilyStore.java:1674) 
at org.apache.cassandra.db.PagedRangeCommand.executeLocally(PagedRangeCommand.java:111) 
at org.apache.cassandra.service.StorageProxy$LocalRangeSliceRunnable.runMayThrow(StorageProxy.java:1418) 
at org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:1931) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) 
at java.lang.Thread.run(Thread.java:744) 

這裏是我使用模式：

CREATE KEYSPACE session WITH replication= {'class': 'SimpleStrategy', 'replication_factor': 1}; 

CREATE TABLE session_data (
username text, 
session_id text, 
app_name text, 
account text, 
last_access timestamp, 
created_on timestamp, 
PRIMARY KEY (username, session_id, app_name, account) 
); 

create index sessionIndex ON session_data (session_id); 
create index sessionAppName ON session_data (app_name); 
create index lastAccessIndex ON session_data (last_access); 

我想知道表定義/索引或查詢本身是否有問題。任何幫助/見解將不勝感激。

Answer 1

它看起來像你絆倒在卡桑德拉的錯誤。這裏是卡桑德拉來源的斷言和相關評論：

/* 
* This method assumes the IndexExpression names are valid column names, which is not the 
* case with composites. This is ok for now however since: 
* 1) CompositeSearcher doesn't use it. 
* 2) We don't yet allow non-indexed range slice with filters in CQL3 (i.e. this will never be 
* called by CFS.filter() for composites). 
*/ 
assert !(cfs.getComparator() instanceof CompositeType); 

此代碼是卡桑德拉-2.0.4和幹線之間修改票CASSANDRA-5417的一部分，但目前還不清楚，我認爲作者意識到這個問題。斷言已被刪除，但評論不是。我會建議向Cassandra項目提交一個錯誤報告。