@hequn8128 I'm pretty sure that what you have just pointed out is bug in Flink SQL. I'm not 100% sure (maybe 95%), but when comparing different types like `CHAR(3)` with `CHAR(5)` or `VARCHAR(2)`, all of the operands should be first converted to same type (adding/ignoring padding when necessary) and only then compared.
In other words `'A ' == 'A'` should return true, and this PR is not a proper fix to this problem. It doesn't fix for example: ``` SELECT * FROM country WHERE country_name = 'GERMANY ' ``` This further convinces me that: > and our CHAR(x) support seems to be broken (for example 'A ' || 'B ' should > return 'A B ') Probably either we should convert string literals to `VARCHAR` or properly implement support for `CHAR` [ Full content available at: https://github.com/apache/flink/pull/6519 ] This message was relayed via gitbox.apache.org for [email protected]
