What does SimpleJDBCTemplate.queryForInt do when the database returns null?

Question

What does SimpleJDBCTemplate.queryForInt do when the SQL query's actual result is null?

In particular, what happens if I run queryForInt("select max(foo) from f") and f has no rows?

While I'm on this subject, what happens if I run queryForInt("select foo from f") and f has no rows?

Answer 1

If the query returns null, the queryForInt method will return 0. However, if the query returns no rows, or returns more than one row, queryForInt will throw an IncorrectResultSizeDataAccessException.

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