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ouyangwulin commented on FLINK-35740: ------------------------------------- [~seung-min] As this ticket describe,I have some Questtion. # why we only supported mysql? # Can we do the support configuration to discover primarykeys first, before discovering unique indexes, if neither of these indexes should be supported? > [mysql] Allow column as chunk key even if not in Primary Keys > ------------------------------------------------------------- > > Key: FLINK-35740 > URL: https://issues.apache.org/jira/browse/FLINK-35740 > Project: Flink > Issue Type: Improvement > Components: Flink CDC > Reporter: Lee SeungMin > Priority: Major > Labels: pull-request-available > > PR: [[FLINK-35740] Allow column as chunk key even if not in Primary Keys by > SML0127 · Pull Request #3448 · apache/flink-cdc > (github.com)|https://github.com/apache/flink-cdc/pull/3448] > Allow column as chunk key even if it is not in the primary keys. > > There are cases where the primary key is not a numeric type, such as varchar > or varbinary. > In this case, the `distributed factor` and `chunk range` may be calculated > incorrectly, resulting in one chunk containing too many records. > But there was no conditions for restrict type for primary keys or chunk key > columns, so this may cause out of memory in the task manager. > Actually, in our company, there was a mysql tables that PK is a varbinary > column and the above situation occurred. -- This message was sent by Atlassian Jira (v8.20.10#820010)