Hequn Cheng created FLINK-9559: ---------------------------------- Summary: The type of a union of CHAR columns of different lengths should be VARCHAR Key: FLINK-9559 URL: https://issues.apache.org/jira/browse/FLINK-9559 Project: Flink Issue Type: Improvement Components: Table API & SQL Reporter: Hequn Cheng Assignee: Hequn Cheng
Currently, If the case-when expression has two branches which return string literal, redundant white spaces will be appended to the short string literal. For example, for the sql: case 1 when 1 then 'a' when 2 then 'bcd' end, the return value will be 'a ' of CHAR(3) instead of 'a'. Although, this follows the behavior in strict SQL standard mode(SQL:2003). We should get the pragmatic return type in a real scenario without blank-padded. Happily, this problem has been fixed by [CALCITE-2321|https://issues.apache.org/jira/browse/CALCITE-2321], we can upgrade calcite to the next release(1.17.0) and override {{RelDataTypeSystem}} in flink to configure the return type, i.e., making {{shouldConvertRaggedUnionTypesToVarying()}} return true. -- This message was sent by Atlassian JIRA (v7.6.3#76005)