[
https://issues.apache.org/jira/browse/FLINK-27275?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17524674#comment-17524674
]
Shengkai Fang edited comment on FLINK-27275 at 4/20/22 3:17 AM:
----------------------------------------------------------------
If we want to propose a general solution, it's better to introduce a new SQL
syntax to allow users to determine the behavior rather than the storage
implementation. Using the new syntax, the planner has the ability to tell the
sink whether to overwrite the whole rows or update the rows with the specified
columns in the SQL.
was (Author: fsk119):
If we want to propose a general solution, it's better to introduce a new SQL
syntax to allow users to determine the behavior rather than the storage
implementation. Using the new syntax, the planner has the ability to tell the
sink whether to overwrite the whole rows or update the rows with the specified
columns in the SQL. I think more infos are required before getting the
conclusion.
> Support partial insert in flink-connector-jdbc
> ----------------------------------------------
>
> Key: FLINK-27275
> URL: https://issues.apache.org/jira/browse/FLINK-27275
> Project: Flink
> Issue Type: New Feature
> Components: Connectors / JDBC
> Affects Versions: 1.14.3
> Reporter: Fangliang Liu
> Priority: Major
>
> I use the following statement to create a flink job.
> a field in the source data is null, but the field in mysql is not null, then
> the field will be overwritten by null after the record is written to the
> database. If I don't want this historical value to be overwritten by null, it
> is necessary to take out the historical value in the database in this task,
> and then update it to the database again, which is very costly for us.
> So, i think the choice of whether to update to the database if a field is
> null can actually be left to the use.
> {code:java}
> CREATE TABLE IF NOT EXISTS t_source (
> `user_id` bigint,
> `A` string,
> `B` string,
> `C` string,
> `flag` varchar(256)
> )WITH (
> 'connector' = 'kafka',
> 'format' = 'canal-json',
> 'scan.startup.mode' = 'latest-offset',
> ... ...
> );
> CREATE TABLE IF NOT EXISTS t_sink (
> `user_id` bigint,
> `A` string,
> `B` string,
> `C` string,
> `flag` varchar(256),
> PRIMARY KEY (`user_id`) NOT ENFORCED
> )WITH (
> 'connector' = 'jdbc',
> 'url' = 'jdbc:mysql://xx.xx.xx.xx:xxx/test',
> 'table-name' = 'user',
> ... ...
> );
> INSERT INTO t_sink(
> `user_id`,
> `A`,
> `B`,
> `C`,
> `flag`
> ) SELECT `user_id`, `A`, `B`, `C`, `flag` FROM t_source;
> {code}
>
--
This message was sent by Atlassian Jira
(v8.20.7#820007)
