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1.生产测试数据
# vim /Users/lcc/IdeaProjects/AllTest/data/hive/udf/littlebigdata.txt
lcc,lcc@123.com,2-12-1981,209.191.139.200,M,10
xjj,xjj@rsa.com,10-10-2004,10.10.10.1,M,50
ser,ser@dfg.com,4-5-1974,64.64.5.1,F,2
2.开启hive
lcc@lcc ~$ hive --service metastore
lcc@lcc ~$ hive --service hiveserver23.远程连接hive(可以直接hive)
lcc@lcc ~$ beeline -u "jdbc:hive2://lcc:10013"
0: jdbc:hive2://lcc:10013> use lccdb;
No rows affected (0.179 seconds)
0: jdbc:hive2://lcc:10013> create table if not exists litt(name string,email string,body string,ip string,gendr string ,anum int) row format delimited fields terminated by ',';
0: jdbc:hive2://lcc:10013> load data local inpath '/Users/lcc/IdeaProjects/AllTest/data/hive/udf/littlebigdata.txt';
: jdbc:hive2://lcc:10013> select * from litt;
+------------+--------------+-------------+------------------+-------------+------------+--+
| litt.name | litt.email | litt.body | litt.ip | litt.gendr | litt.anum |
+------------+--------------+-------------+------------------+-------------+------------+--+
| lcc | [email protected] | 2-12-1981 | 209.191.139.200 | M | 10 |
| xjj | [email protected] | 10-10-2004 | 10.10.10.1 | M | 50 |
| ser | [email protected] | 4-5-1974 | 64.64.5.1 | F | 2 |
+------------+--------------+-------------+------------------+-------------+------------+--+
3 rows selected (0.618 seconds)
0: jdbc:hive2://lcc:10013>4.编写代码
package com.hive.udf.example;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.io.Text;
/**
* Created by lcc on 2018/8/17.
*/
public class HelloUDF extends UDF {
public Text evaluate(Text body){
return new Text("hello"+body);
}
public static void main(String[] args){
HelloUDF udf = new HelloUDF();
Text result = udf.evaluate(new Text("张三"));
System.out.println(result.toString());
}
}
5.编译
lcc@lcc hive_test$ mvn clean package6.注册临时函数UDF
0: jdbc:hive2://lcc:10013> add jar /Users/lcc/IdeaProjects/AllTest/hive_test/target/hive_test-1.0-SNAPSHOT.jar;
0: jdbc:hive2://lcc:10013> list jars;
+------------------------------------------------------------------------------+--+
| resource |
+------------------------------------------------------------------------------+--+
| /Users/lcc/IdeaProjects/AllTest/hive_test/target/hive_test-1.0-SNAPSHOT.jar |
+------------------------------------------------------------------------------+--+
3 rows selected (0.017 seconds)
0: jdbc:hive2://lcc:10013>
0: jdbc:hive2://lcc:10013> create temporary function say_hello as 'com.hive.udf.example.HelloUDF';
0: jdbc:hive2://lcc:10013> show functions like 'say*';
+------------+--+
| tab_name |
+------------+--+
| say_hello |
+------------+--+
1 row selected (0.084 seconds)
0: jdbc:hive2://lcc:10013>
0: jdbc:hive2://lcc:10013> select name,body,say_hello(body) from litt;
+-------+-------------+------------------+--+
| name | body | _c2 |
+-------+-------------+------------------+--+
| lcc | 2-12-1981 | hello2-12-1981 |
| xjj | 10-10-2004 | hello10-10-2004 |
| ser | 4-5-1974 | hello4-5-1974 |
+-------+-------------+------------------+--+
3 rows selected (0.51 seconds)
0: jdbc:hive2://lcc:10013>