摘要：
试试在DBOutputFormat 的Reducer 阶段有几十万的记录要插入，就会报错内存溢出。可以尝试 在mapred-site.xml 里面修改 mapred.child.java.opts -Xmx512m Java opts for the task tracker child processes. The following symbol, if present, will be interpolated: @taskid@ is replaced by current TaskID. Any other occurrences of '@' will go un. 阅读全文
摘要：
今天弄个MapRecord 去数据库取数据 发现一直报错，13/08/07 14:54:47 INFO mapred.JobClient: Task Id : attempt_201308070937_0009_m_000000_0, Status : FAILEDjava.io.IOException: ORA-00933: SQL command not properly ended at org.apache.hadoop.mapred.lib.db.DBInputFormat.getRecordReader(DBInputFormat.java:289) at org.apache.h 阅读全文