我有一个指数m_idx上(k1,k2,k3) 如果我做 SELECT c1,c2,c3... FROM tb FORCE INDEX (m_idx) WHERE k1=500 AND k2 IN(...) AND k2>2000 ORDER BY k1 LIMIT 1000; OR SELECT c1,c2,c3... FROM tb FORCE INDEX (m_idx) WHERE k1 IN
Hadoop的DistributedCache文档似乎并未充分描述如何使用分布式缓存。这里给出的例子: // Setting up the cache for the application
1. Copy the requisite files to the FileSystem:
$ bin/hadoop fs -copyFromLocal lookup.dat /myapp/look