[FLINK-33069]Mysql and Postgres catalog support url extra parameters

[waywtdcc]

Mysql and Postgres catalog support url extra parameters

CREATE CATALOG mymysql WITH(
'type' = 'jdbc',
'default-database' = 'test',
'username' = 'root',
'password' = 'xxx',
'base-url' = 'jdbc:mysql://xxx:53309',
'extra-url-param' = '?characterEncoding=utf8'
);

If used in this way, the URLs of all tables obtained from this catalog are: jdbc:mysql://xxx:53309?characterEncoding=utf8

[boring-cyborg]

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[waywtdcc]

@MartijnVisser Hello, can you review this PR when you have time?

[MartijnVisser]

@waywtdcc Why does this need to be an additional parameter?

[waywtdcc]

@waywtdcc Why does this need to be an additional parameter?

Because sometimes you need to use ?characterEncoding=utf8 similar url parameters to connect to jdbc

[MartijnVisser]

Because sometimes you need to use ?characterEncoding=utf8 similar url parameters to connect to jdbc

But why not just pass these in to the base URL?

[waywtdcc]

Because sometimes you need to use ?characterEncoding=utf8 similar url parameters to connect to jdbc

But why not just pass these in to the base URL?

The real url is a combination of base-url+default-database, so I cannot form the correct url when I add it to base-url. For example, if the base-url is set to jdbc:mysql://xxx:53309?characterEncoding=utf8, then the final real url is jdbc:mysql://xxx:53309?characterEncoding=utf8/test; this is the wrong url.