Insert Default

[billy1624]

PR Info

• Required by Insert Default - Inserting ActiveModel with all attributes NotSet sea-orm#432
• Related to Failed to insert row with only default values sea-orm#420
• REF
  • MySQL: https://dev.mysql.com/doc/refman/8.0/en/insert.html
  • PostgreSQL: https://www.postgresql.org/docs/9.1/dml-insert.html
  • SQLite: https://www.sqlite.org/lang_insert.html

[tyt2y3]

I totally think that the above API behaviour is too smart, the following should be better.
There is no basis that the query builder just assumes that DEFAULT VALUES is valid for the table either.

assert_eq!(
    Query::insert()
        .into_table(Glyph::Table)
        .or_default_values()
        .to_string(PostgresQueryBuilder),
    "INSERT INTO \"glyph\" DEFAULT VALUES"
);
assert_eq!(
    Query::insert()
        .into_table(Glyph::Table)
        .columns(vec![Glyph::Image])
        .values_panic(vec!["ABC".into()])
        .or_default_values()
        .to_string(PostgresQueryBuilder),
    "INSERT INTO \"glyph\" (\"image\") VALUES ('ABC')"
);