[FLINK-18002] Support forcing varchar type in Json format

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.12.0
• Component/s: Formats (JSON, Avro, Parquet, ORC, SequenceFile)
• Labels: pull-request-available
• Assignee: Benchao Li
• Reporter: Benchao Li
• Created: 28/May/20 11:42
• Updated: 13/Jul/20 15:20
• Resolved: 13/Jul/20 15:20

Description

Currently in json format, if the field type is varchar, we will call `JsonNode.asText()` which we always assumes the JsonNode is a TextNode.

However, in many cases, we want to force it as varchar for other types, etc ObjectNode. We should use `JsonNode.toString()` for other JsonNode instead of `JsonNode.asText()`.

Issue Links

• links to: GitHub Pull Request #12421
• links to: User Case 1