[FLINK-17153] flink sql convert constant to char type cause loop

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 1.9.1
• Component/s: Table SQL / Planner
• Assignee: Unassigned
• Reporter: xiaodao
• Created: 15/Apr/20 08:21
• Updated: 15/Apr/20 13:17
• Resolved: 15/Apr/20 13:17

Description

sql:

SELECT
 '公开发债' AS secondary_business
FROM VarBondCode
WHERE stock_type = '77';

code is:

org.apache.flink.table.planner.codegen.CodeGeneratorContext#addReusableStringConstants

when it parse constant, it change to unicode, and str length is change, in this case secondary_business is char(4), and after  change it become '_UTF-16LE'\u516C\u5F00\u53D1\u503A''.

calcite call makecast func can't remove it,and call it loop;

org.apache.calcite.rex.RexBuilder#canRemoveCastFromLiteral

 

 

Issue Links

• is duplicated by: FLINK-16113 ExpressionReducer shouldn't escape the reduced string value