卡桑德拉二級索引的問題 - 返回零行

Question

我有一個問題，即二級指標在Cassandra是返回零行：

我沿着入門文檔如下：

http://www.datastax.com/documentation/getting_started/doc/getting_started/gettingStartedCQL.html

在此基礎上，我有以下卡桑德拉腳本

 
/* hello.cql */ 
drop keyspace test; 
CREATE KEYSPACE test WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 }; 
use test; 
CREATE TABLE users ( user_id int PRIMARY KEY, fname text, lname text); 
DESCRIBE TABLES; 
INSERT INTO users (user_id, fname, lname) 
    VALUES (1745, 'john', 'smith'); 
INSERT INTO users (user_id, fname, lname) 
    VALUES (1744, 'john', 'doe'); 
INSERT INTO users (user_id, fname, lname) 
    VALUES (1746, 'john', 'smith'); 
SELECT * FROM users; 
CREATE INDEX ON users (lname); 

/* These queries both return 0 rows ??? */ 
SELECT * FROM users WHERE lname = 'smith'; 
SELECT * FROM users WHERE lname = 'doe'; 

但是......

 
cqlsh < hello.cql 

users 


user_id | fname | lname 
---------+-------+------- 
    1745 | john | smith 
    1744 | john | doe 
    1746 | john | smith 

(3 rows) 

(0 rows) 

(0 rows) 

這應該是直截了當的 - 我錯過了什麼嗎？

Answer 1

對於2個SELECT查詢返回的結果將意味着CREATE INDEX將執行同步和將現有的所有數據後僅回報將被編入索引。

如果更改腳本中的順序以在插入任何數據之前定義索引，我希望2選擇返回結果。

Answer 2

使用Cassandra 2.1.0，無論索引是在插入數據之前還是之後創建，我都會得到結果。

 
    Connected to Test Cluster at 127.0.0.1:9042. 
    [cqlsh 5.0.1 | Cassandra 2.1.0 | CQL spec 3.2.0 | Native protocol v3] 
    Use HELP for help. 
    cqlsh> 
    cqlsh> CREATE KEYSPACE test WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 }; 
    cqlsh> use test; 
    cqlsh:test> CREATE TABLE users ( user_id int PRIMARY KEY, fname text, lname text); 
    cqlsh:test> INSERT INTO users (user_id, fname, lname) 
     ... VALUES (1745, 'john', 'smith'); 
    cqlsh:test> INSERT INTO users (user_id, fname, lname) 
     ... VALUES (1744, 'john', 'doe'); 
    cqlsh:test> INSERT INTO users (user_id, fname, lname) 
     ... VALUES (1746, 'john', 'smith'); 
    cqlsh:test> CREATE INDEX ON users (lname); 
    cqlsh:test> SELECT * FROM users WHERE lname = 'smith'; 

    user_id | fname | lname 
    ---------+-------+------- 
     1745 | john | smith 
     1746 | john | smith 

    (2 rows) 

    cqlsh:test> SELECT * FROM users WHERE lname = 'doe'; 

    user_id | fname | lname 
    ---------+-------+------- 
     1744 | john | doe 

    (1 rows) 

Answer 3

下面是我的安裝平臺和版本信息：

 
john@piggies:~/Dropbox/source/casandra$ nodetool -h localhost version 
ReleaseVersion: 2.0.10 
john@piggies:~/Dropbox/source/casandra$ lsb_release -a 
No LSB modules are available. 
Distributor ID: Ubuntu 
Description: Ubuntu 14.04.1 LTS 
Release: 14.04 
Codename: trusty 
john@piggies:~/Dropbox/source/casandra$ ^C 
john@piggies:~/Dropbox/source/casandra$