Cassandra：基于“timeuuid where条件”选择记录

Question

我在Cassandra中创建了一张表，并想根据列的timeuuid类型的where条件选择数据。

CREATE TABLE shahid.stock_ticks(
symbol varchar,
date int,
trade timeuuid,
trade_details text,
PRIMARY KEY (  (symbol, date), trade   )
) WITH CLUSTERING ORDER BY (trade DESC) ;

INSERT INTO shahid.stock_ticks (symbol, date, trade, trade_details) VALUES ('NFLX', 1, now(), 'this is 10' );
INSERT INTO shahid.stock_ticks (symbol, date, trade, trade_details) VALUES ('NFLX', 1, now(), 'this is 2' );
INSERT INTO shahid.stock_ticks (symbol, date, trade, trade_details) VALUES ('NFLX', 1, now(), 'this is 3' );

上面的查询已经插入了记录，其中一个记录在交易列中有值'2045d660-9415-11e5-9742-c53da2f1a8ec'。

我想这样选择，但是它报错了。

select * from shahid.stock_ticks  where symbol = 'NFLX' and date = 1 and trade < '2045d660-9415-11e5-9742-c53da2f1a8ec';

下面显示了错误信息：

InvalidQueryException: 对于类型为timeuuid的“trade”，字符串常量无效（2045d660-9415-11e5-9742-c53da2f1a8ec ）

我尝试了以下查询，但没有成功。

select * from shahid.stock_ticks  where symbol = 'NFLX' and date = 1 and trade < maxTimeuuid('2045d660-9415-11e5-9742-c53da2f1a8ec');
select * from shahid.stock_ticks  where symbol = 'NFLX' and date = 1 and trade < dateOf('2045d660-9415-11e5-9742-c53da2f1a8ec');
select * from shahid.stock_ticks  where symbol = 'NFLX' and date = 1 and trade < unixTimestampOf('2045d660-9415-11e5-9742-c53da2f1a8ec');

- Mohd Shahid

Answer 1

移除您的UUID周围的引号。Cassandra原生支持它们，而不是通过字符串。

select * from shahid.stock_ticks  where symbol = 'NFLX' and date = 1 and trade < 2045d660-9415-11e5-9742-c53da2f1a8ec;

- Jan Dörrenhaus