使用flinksql读取parquent文件

た入场券 2022-10-05 11:43 324阅读 0赞

# 使用flinksql读取parquent文件 #

## 一、导入maven依赖 ##

<dependency>
           <groupId>org.apache.flink</groupId>
           <artifactId>flink-parquet_2.12</artifactId>
           <version>1.11</version>
     </dependency>

## 二、创建flink动态表关联文件 ##

public static void main(String[] args) { 
    
            final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
            env.setParallelism(2);
            final StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
            
            String dataPath = "/Users/klook/Downloads/user_profile/";
            
    
            tableEnv.executeSql("CREATE TABLE `user_profile_data`(\n" +
                    " `device_id` STRING,\n" +
                    " `last_week_click_num` INT ," +
                    " `last_month_click_num` INT ," +
                    " `last_week_searchpv` INT ," +
                    " `year` string, " +
                    " `month` string, " +
                    " `day` string " +
                    ") partitioned by(`year`,`month`,`day`)" +
                    " WITH ( " +
                    " 'connector' = 'filesystem',\n" +
                    " 'path' = "+ "'" + dataPath + "',\n" +
                    " 'format' = 'parquet'\n" +
                    " )");
    
    
            final Table activity_base = tableEnv.sqlQuery(sql);
            final DataStream<Row> activityBaseStream = tableEnv.toAppendStream(activity_base, Row.class);
            sink2Mongo(activityBaseStream);
    
    
            try { 
                env.execute();
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }

关联后可以使用sql进行操作，也可以转换成流进行别的操作。

## 三、特殊说明 ##

如果在生产环境使用jar进行执行时报没有parquet工厂类的时候，可以将parquet的jar包放到flink的lib目录下。

org.apache.flink.client.program.ProgramInvocationException: The main method caused an error: Could not find any factory for identifier 'parquet' that implements 'org.apache.flink.table.factories.FileSystemFormatFactory' in the classpath.
    Available factory identifiers are:
    csv
    json
    	at org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:302)
    	at org.apache.flink.client.program.PackagedProgram.invokeInteractiveModeForExecution(PackagedProgram.java:198)
    	at org.apache.flink.client.ClientUtils.executeProgram(ClientUtils.java:149)
    	at org.apache.flink.client.cli.CliFrontend.executeProgram(CliFrontend.java:699)
    	at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:232)
    	at org.apache.flink.client.cli.CliFrontend.parseParameters(CliFrontend.java:916)
    	at org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:992)
    	at java.security.AccessController.doPrivileged(Native Method)
    	at javax.security.auth.Subject.doAs(Subject.java:422)
    	at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1926)
    	at org.apache.flink.runtime.security.contexts.HadoopSecurityContext.runSecured(HadoopSecurityContext.java:41)
    	at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:992)
    Caused by: org.apache.flink.table.api.ValidationException: Could not find any factory for identifier 'parquet' that implements 'org.apache.flink.table.factories.FileSystemFormatFactory' in the classpath.

如果报以下错，可以检查分区字段是否在sql语句里面。

Caused by: java.lang.ArrayIndexOutOfBoundsException: -1
    	at org.apache.flink.formats.parquet.ParquetFileSystemFormatFactory$ParquetInputFormat.lambda$open$0(ParquetFileSystemFormatFactory.java:171)
    	at java.util.LinkedHashMap.forEach(LinkedHashMap.java:684)
    	at org.apache.flink.formats.parquet.ParquetFileSystemFormatFactory$ParquetInputFormat.open(ParquetFileSystemFormatFactory.java:169)
    	at org.apache.flink.formats.parquet.ParquetFileSystemFormatFactory$ParquetInputFormat.open(ParquetFileSystemFormatFactory.java:128)
    	at org.apache.flink.streaming.api.functions.source.InputFormatSourceFunction.run(InputFormatSourceFunction.java:85)
    	at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:100)
    	at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:63)
    	at org.apache.flink.streaming.runtime.tasks.SourceStreamTask$LegacySourceFunctionThread.run(SourceStreamTask.java:213)
    Command exiting with ret '0'