haruki-830 commented on code in PR #4492: URL: https://github.com/apache/flink-cdc/pull/4492#discussion_r3755830185
########## docs/content.zh/docs/core-concept/transform.md: ########## @@ -244,11 +244,15 @@ Flink CDC 使用 [Calcite](https://calcite.apache.org/) 来解析表达式并且 | CASE WHEN condition1 THEN result1 (WHEN condition2 THEN result2)* (ELSE result_z) END | 嵌套三元表达式 | 当第一个 conditionX 满足时，返回 resultX。如果没有条件满足，如果提供了 result_z 则返回 result_z，否则返回 NULL。 | | COALESCE(value1 [, value2]*) | coalesce(Object... objects) | 返回第一个不为 NULL 的参数。如果所有参数都为 NULL，则返回 NULL。返回类型是所有参数中限制最少的公共类型。如果所有参数都可为空，则返回类型也可为空。 | | IF(condition, true_value, false_value) | condition ? true_value : false_value | 如果条件满足，返回 true_value，否则返回 false_value。例如，IF(5 > 3, 5, 3) 返回 5。 | +| IFNULL(value, replacement) | ifNull(value, replacement) | 当 value 为 NULL 时返回 replacement，否则返回 value。两个参数必须存在公共类型。仅当 replacement 可为 NULL 时，结果才可为 NULL。 | +| NULLIF(value1, value2) | nullIf(value1, value2) | 当 value1 与 value2 相等时返回 NULL，否则返回 value1。返回类型为 value1 对应的可空类型。 | Review Comment: Thanks for pointing this out! [FLINK-40203](https://issues.apache.org/jira/browse/FLINK-40203) / PR [#4484](https://github.com/apache/flink-cdc/pull/4484) is introducing an opt-in `FLINK_SQL` expression semantics mode, under which `=` compares numeric operands across numeric types and is therefore consistent with `NULLIF`. The default mode intentionally preserves the existing type-sensitive `=` behavior for backward compatibility. In the latest commit, I have documented this difference rather than duplicating the comparison-semantics changes from FLINK-40203. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
