to use hadoop vs rdbms

GetData()throwsIOException {Configuration config = hbaseconfiguration.create (); Config.set ("Hbase.zookeeper.quorum","172.31.25.8,172.31.25.2,172.31.25.3"); Htable htable =Newhtable (config,"Qyk_info"); Get get =NewGet (Bytes.tobytes ("1")); Result result = Htable.get (get); String age = bytes.tostring (Result.getvalue (Bytes.tobytes ("Info"), Bytes.tobytes ("Age"))); String name = bytes.tostring (Result.getvalue (Bytes.tobytes ("Info"), Bytes.tobytes ("Name"))); String id = bytes.tostr

methods:/** Rewrite the mapper setup method to get the files in the distributed cache*/@Overrideprotected voidSetup (mapper. Context context)throwsIOException, interruptedexception {//TODO auto-generated Method Stub Super. Setup (context); Uri[] Cachefile=Context.getcachefiles (); Path Tagsetpath=NewPath (cachefile[0]); Path Tagedurlpath=NewPath (cachefile[1]); File operations (such as reading the contents into set or map); } @Override Public voidmap (longwritable key, Text value, con

, rainfall, etc.), you should select the multi-reduce mode. The map phase is responsible for collating the input data, and the reduce phase is responsible for implementing the core algorithm of the index product. Specific calculation processes such as:2) Product production algorithm with high complexityfor the high complexity of remote sensing product production algorithm, a MapReduce computing task is often difficult to meet the production requirements, you need to

The mapreduce program we write is not necessarily efficient. We need to determine where the mapreduce bottleneck is. The hadoop Framework provides support for hprof. hprof can track CPU usage, heap usage, and thread lifecycles, which can be of great help for determining program bottlenecks. To use hprof, we need to make some settings in jobconf. The specific operations are as follows: Jobconf = new jobconf

the Zookeeper directory　　　　　　　　　　　　Copy this path, and then go to config file to modify this, and the rest do not need to be modified　　　　　　　　　　　　After the configuration is complete, start zookeeper, and in the Zookeeper directory, execute the command: bin/zkserver.sh start　　　　　　　　　　　　View zookeeper status can be seen as a stand-alone node　　　　　　command to enter the client: bin/zkcli.sh　　　　　　To create a command for a node:Create/test "Test-data"　　　　　　View node Command LS/　　　　　　Gets the node comma

BackgroundCompany data processing has two computing frames, single frame and Mr Framework. Now I've abstracted a set of API interface for business computing developers to use.The operation schedule of API is implemented in two computing frames respectively. The application developer has time to upload the override configuration file. To adjust the number of business calculation parameters. The stand-alone framework is easy to implement. However, in the Mr Framework, the distribution of the overr

statement)Sqoop Import--connect jdbc:mysql://192.168.1.10:3306/itcast--username root--password 123 \--query ' SELECT * from Trade_detail where ID > 2 and $CONDITIONS '--split-by trade_detail.id--target-dir '/sqoop/td3 'Note: If you use the--query command, it is important to note that the argument after the where, and $CONDITIONS This parameter must be addedAnd there is the difference between single and double quotes, if--query is followed by double q