有什么方法可以让我们看到在 kafka 中运行流/表的查询？答案

【问题标题】：Is there any way by which we can see query running for stream/ table in kafka?有什么方法可以让我们看到在 kafka 中运行流/表的查询？
【发布时间】：2020-01-17 19:28:58
【问题描述】：

我想查看在 Kafka 中为我的流/表运行的查询。

Create stream foo as select * from bar where distuinguisher='xxx';

 Message                    
----------------------------
 Stream created and running 
----------------------------

一旦有人创建了流/表，我就只能查询流/表。有什么方法可以让我看到流背后的逻辑或完整的查询。

【问题讨论】：

标签： apache-kafka ksqldb confluent-platform

【解决方案1】：

DESCRIBE EXTENDED 将为您提供此信息。您还可以使用SHOW QUERIES 查看所有正在运行的查询。

例如：

ksql> DESCRIBE EXTENDED FOO;

Name                 : FOO
Type                 : STREAM
Key field            :
Key format           : STRING
Timestamp field      : Not set - using <ROWTIME>
Value format         : JSON
Kafka topic          : FOO (partitions: 1, replication: 1)

 Field   | Type
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ROWTIME | BIGINT           (system)
 ROWKEY  | VARCHAR(STRING)  (system)
 LOGGER  | VARCHAR(STRING)
 LEVEL   | VARCHAR(STRING)
 TIME    | BIGINT
 MESSAGE | STRUCT<TYPE INTEGER, DESERIALIZATIONERROR STRUCT<ERRORMESSAGE VARCHAR(STRING), RECORDB64 VARCHAR(STRING), CAUSE ARRAY<VARCHAR(STRING)>>, RECORDPROCESSINGERROR STRUCT<ERRORMESSAGE VARCHAR(STRING), RECORD VARCHAR(STRING), CAUSE ARRAY<VARCHAR(STRING)>>, PRODUCTIONERROR STRUCT<ERRORMESSAGE VARCHAR(STRING)>>
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Queries that write from this STREAM
-----------------------------------
CSAS_FOO_1 : CREATE STREAM FOO WITH (KAFKA_TOPIC='FOO', PARTITIONS=1, REPLICAS=1) AS SELECT *
FROM KSQL_PROCESSING_LOG KSQL_PROCESSING_LOG
EMIT CHANGES;

For query topology and execution plan please run: EXPLAIN <QueryId>

Local runtime statistics
------------------------


(Statistics of the local KSQL server interaction with the Kafka topic FOO)
ksql>

ksql> SHOW QUERIES;

 Query ID   | Kafka Topic | Query String
-------------------------------------------------------------------------------------------------------------
 CSAS_FOO_1 | FOO         | CREATE STREAM FOO WITH (KAFKA_TOPIC='FOO', PARTITIONS=1, REPLICAS=1) AS SELECT *
FROM KSQL_PROCESSING_LOG KSQL_PROCESSING_LOG
EMIT CHANGES;
-------------------------------------------------------------------------------------------------------------
For detailed information on a Query run: EXPLAIN <Query ID>;
ksql>

【讨论】：