【发布时间】:2018-11-06 11:21:42
【问题描述】:
我有以下 Cassandra 表:
CREATE TABLE myflights.flights_by_airport2 (
origin text,
dep_time timestamp,
fl_date timestamp,
airline_id int,
carrier text,
fl_num int,
PRIMARY KEY ((origin), dep_time)
) WITH CLUSTERING ORDER BY (dep_time ASC);
cqlsh:myflights> select * from flights_by_airport2 limit 5;
origin | dep_time | airline_id | carrier | fl_date | fl_num
--------+---------------------------------+------------+---------+---------------------------------+--------
MSY | 2012-01-01 05:57:00.000000+0000 | 19977 | UA | 2012-01-01 00:00:00.000000+0000 | 275
MSY | 2012-01-01 06:01:00.000000+0000 | 20409 | B6 | 2012-01-01 00:00:00.000000+0000 | 110
MSY | 2012-01-01 06:13:00.000000+0000 | 19790 | DL | 2012-01-01 00:00:00.000000+0000 | 551
MSY | 2012-01-01 06:45:00.000000+0000 | 19805 | AA | 2012-01-01 00:00:00.000000+0000 | 1190
MSY | 2012-01-01 06:46:00.000000+0000 | 19977 | UA | 2012-01-01 00:00:00.000000+0000 | 1184
以下语句不返回任何数据:
cqlsh:myflights> select * from flights_by_airport2 where origin = 'MSY';
origin | dep_time | airline_id | carrier | fl_date | fl_num
--------+----------+------------+---------+---------+--------
(0 rows)
我在 Ubuntu 虚拟机上安装了单节点 Cassandra 和 Spark(DSE 6 集群)。
【问题讨论】:
-
我会首先通过运行
where origin contains 'MSY'来检查是否是空白问题 -
我从源文件中删除了所有前导空格并刷新了 Cassandra 表。现在可以了。干杯!
标签: scala apache-spark cassandra apache-spark-sql datastax-enterprise