Support batchUpdate in JdbcClient

[making]

JdbcClient introduced in #30931 is missing batchUpdate method

[jhoeller]

This is intentional since batchUpdate is a rather awkward method to provide parameters for... in a JdbcClient style. From a design perspective, JdbcClient is a more convincing arrangement if it just addresses individual statement executions.

Also, we got SimpleJdbcInsert in the same package providing a sophisticated arrangement for batch inserts as well. On a related note, SimpleJdbcCall provides a similar arrangement for stored procedure calls which JdbcClient does not cover either. Alternatively, there is always JdbcTemplate itself for custom batch update needs.

In terms of broader alignment, DatabaseClient does not provide support for batch updates either. Granted, R2DBC comes with a different arrangement there but equally hard to parameterize in a fluent style, as far as I'm concerned.

[hantsy]

Yesterday I was just confused why lacks batch update in JdbcClient .

So the the solution is SimpleJdbcInsert?

[making]

you can use JdbcTemplate for batchUpdate directly

[shirishpandharikar]

Is there a possibility to expose the underlying JdbcTemplate or NamedParameterJdbcTemplate from the JdbcClient. Instead of having both JdbcClient and JdbcTemplate or NamedParameterJdbcTemplate it would be good if both of them can be accessed and batch operation be executed.

[IgnatBeresnev]

Definitely agree with @shirishpandharikar

• I'm unable to use SimpleJdbcInsert since I need to add an "ON CONFLICT ..." to the batch statement
• I don't want to rely on order, so I have to use NamedParameterJdbcTemplate
• For my select queries I use JdbcClient

So I end up injecting both JdbcClient and JdbcTemplate, from which I additionally construct NamedParameterJdbcTemplate where needed.

I'd like to inject only JdbcClient so that my colleagues are not confused whether to use JdbcTemplate, NamedParameterJdbcTemplate or JdbcClient.