[FLINK-14807] Add TableResult#collect api for fetching data to client

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Implemented
• Affects Version/s: 1.9.1
• Fix Version/s: 1.11.0
• Component/s: Table SQL / API
• Labels: pull-request-available usability
• Assignee: Caizhi Weng
• Reporter: Jeff Zhang
• Created: 15/Nov/19 07:01
• Updated: 31/Mar/21 09:01
• Resolved: 18/May/20 09:10

Description

Currently, it is very unconvinient for user to fetch data of flink job unless specify sink expclitly and then fetch data from this sink via its api (e.g. write to hdfs sink, then read data from hdfs). However, most of time user just want to get the data and do whatever processing he want. So it is very necessary for flink to provide api Table#collect for this purpose. 

 

Other apis such as Table#head, Table#print is also helpful.  

 

Issue Links

• blocks: FLINK-17146 Support conversion between PyFlink Table and Pandas DataFrame
• duplicates: FLINK-13943 Provide api to convert flink table to java List (blink planner)
• is blocked by: FLINK-15102 Allow users to construct a DataStream from a new Source API
• is blocked by: FLINK-16845 Implement SourceReaderOperator which runs the SourceReader.
• is blocked by: FLINK-16998 Add a changeflag to Row type
• is blocked by: FLINK-17680 Support @ExcludeFromDocumentation in RestAPIDocGenerator
• relates to: FLINK-17252 supports SELECT statement in TableEnvironment#executeSql and Table#execute api
• relates to: FLINK-22047 Could not find FLINSHED Flink job and can't submit job
• links to: GitHub Pull Request #12037
• links to: GitHub Pull Request #12069
• links to: GitHub Pull Request #12073
• links to: GitHub Pull Request #12202

Sub-Tasks

• Add specialized collecting sink function: Closed
• Add specialized collecting iterator: Closed
• Combine collecting sink and iterator to support collecting query results under all execution and network environments: Closed