Sending DEFAULT placeholder via JDBC?

Question

Is it possible to send the box DEFAULTexplicitly through JDBC , as in INSERT INTO sometables VALUES (blah, DEFAULT)? (I'm pretty sure the answer is no, but I'm looking for confirmation from a JDBC expert).

Let's say you had PreparedStatementlike:

INSERT INTO mytable(a, b) VALUES (?, ?)

for table:

CREATE TABLE mytable (
    a integer,
    b integer default some_function()
);

and you wanted to use the database set DEFAULTfor mytable.bsome executions in the package, but not others.

In regular SQL, you should write:

INSERT INTO mytable(a, b) VALUES (1, 42)
INSERT INTO mytable(a, b) VALUES (2, DEFAULT);
...

or of course:

INSERT INTO mytable(a, b) VALUES (1, 42)
INSERT INTO mytable(a) VALUES (2);

... but you cannot do it through JDBC. setString("DEFAULT")of course will not send the keyword DEFAULT, just a literal string 'DEFAULT'.

Is there a way to set the -placeholder parameter, which means DEFAULTin any commonly used drivers?

I see no way to do this with the standard API and spec.

I present something like:

pstmt.setObject(2, Postgresql.DEFAULT, Types.OTHER);

Postgresql.DEFAULT - , setDefault() PreparedStatement.

- ?

Answer 1

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setNull(int, int)

setNull(idx, PostgresTypes.DEFAULT_VALUE)

setNull(int, int, String)

setNull(idx, Types.<correct-field-type>, Postgres.DEFAULT_VALUE_MARKER)

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Answer 2

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