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我跟着this教程和槓桿this github項目,並寫了一個簡單的'mysum'UDF函數。將UDF功能插入Presto的步驟是什麼?
@ScalarFunction("mysum")
@Description("Returns summation of two numbers")
@SqlType(StandardTypes.BIGINT)
public static long sum(@SqlType(StandardTypes.BIGINT) long num1, @SqlType(StandardTypes.BIGINT) long num2)
{
return num1 + num2;
}
我也跟着下面的步驟,以插件的UDF但普雷斯托無法導入該功能。 因爲,關於編寫和插入UDF的文檔很少,所以不勝感激。提前致謝。
- 跑
mvn compile
和mvn package
- 複製
.jar
文件到plugins文件夾下的急板(未壓縮)目錄/Users/nithin/presto-server-0.166/plugin/udfs/
- 開始使用
bin/launcher run
在普雷斯托CLI跑select mysum(10,100)
協調,但會拋出錯誤
當我嘗試在Presto CLI中運行我的UDF('mysum')時,下面是錯誤日誌。 很明顯,Presto無法找到UDF,因此插入不成功。如何解決這個問題?我錯過了任何一步嗎?
➜ Workspaces ./presto.jar --server localhost:8080 --catalog mysql --schema default --debug
presto:default> select mysum(99,100);
Query 20170228_183509_00002_vr5dt failed: line 1:8: Function mysum not registered
com.facebook.presto.sql.analyzer.SemanticException: line 1:8: Function mysum not registered
at com.facebook.presto.sql.analyzer.ExpressionAnalyzer$Visitor.visitFunctionCall(ExpressionAnalyzer.java:824)
at com.facebook.presto.sql.analyzer.ExpressionAnalyzer$Visitor.visitFunctionCall(ExpressionAnalyzer.java:255)
at com.facebook.presto.sql.tree.FunctionCall.accept(FunctionCall.java:111)
at com.facebook.presto.sql.tree.StackableAstVisitor.process(StackableAstVisitor.java:26)
at com.facebook.presto.sql.analyzer.ExpressionAnalyzer$Visitor.process(ExpressionAnalyzer.java:274)
at com.facebook.presto.sql.analyzer.ExpressionAnalyzer.analyze(ExpressionAnalyzer.java:231)
at com.facebook.presto.sql.analyzer.ExpressionAnalyzer.analyzeExpression(ExpressionAnalyzer.java:1406)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.analyzeExpression(StatementAnalyzer.java:1802)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.analyzeSelect(StatementAnalyzer.java:1623)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.visitQuerySpecification(StatementAnalyzer.java:800)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.visitQuerySpecification(StatementAnalyzer.java:188)
at com.facebook.presto.sql.tree.QuerySpecification.accept(QuerySpecification.java:127)
at com.facebook.presto.sql.tree.AstVisitor.process(AstVisitor.java:27)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.visitQuery(StatementAnalyzer.java:550)
at com.facebook.presto.sql.analyzer.StatementAnalyzer.visitQuery(StatementAnalyzer.java:188)
at com.facebook.presto.sql.tree.Query.accept(Query.java:94)
at com.facebook.presto.sql.tree.AstVisitor.process(AstVisitor.java:27)
at com.facebook.presto.sql.analyzer.Analyzer.analyze(Analyzer.java:68)
at com.facebook.presto.sql.analyzer.Analyzer.analyze(Analyzer.java:60)
at com.facebook.presto.execution.SqlQueryExecution.doAnalyzeQuery(SqlQueryExecution.java:290)
at com.facebook.presto.execution.SqlQueryExecution.analyzeQuery(SqlQueryExecution.java:276)
at com.facebook.presto.execution.SqlQueryExecution.start(SqlQueryExecution.java:234)
at com.facebook.presto.execution.QueuedExecution.lambda$start$1(QueuedExecution.java:63)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
select mysum(99,100)