issue_comments

Documentation: - https://sqlite-utils.datasette.io/en/latest/python-api.html#duplicating-tables - https://sqlite-utils.datasette.io/en/latest/reference.html#sqlite_utils.db.Table.duplicate

Learnt that the types in Sqlite-utils differ somewhat from those in Sqlite. I've changed my test to account for this difference and the test has passed successfully. I will submit a PR.

I've written the code and test. Would you be able to advise how to compare table columns in a pytest function properly? Experiencing a challenge when comparing columns.

Test: python def test_duplicate(fresh_db): table = fresh_db.create_table( "table1", { "text_col": str, "float_col": float, "int_col": int, "bool_col": bool, "bytes_col": bytes, "datetime_col": datetime.datetime, }, ) dt = datetime.datetime.now() b = bytes('hello world', 'utf-8') data = {"text_col": "Cleo", "float_col": 3.14, "int_col": -2, "bool_col": True, "bytes_col": b, "datetime_col": str(dt)} table1 = fresh_db["table1"] row_id = table1.insert(data).last_rowid table1.duplicate('table2') table2 = fresh_db["table2"] assert data == table2.get(row_id) assert table1.columns == table2.columns # FAILS HERE

Result:

Failure is due to column types being named differently -- e.g. 'FLOAT' vs 'REAL', 'INTEGER' vs 'INT'. How should I go about comparing columns while accounting for equivalent types?

Or did I miss out something in my duplication code correctly? Here's how I did it: in db.py, I've added the following code: ```python class Table(Queryable): [...] def duplicate( self, name_new: str ) -> "Table": """ Duplicate this table in this database.

    :param name_new: Name of new table.
    """
    assert self.exists()
    with self.db.conn:
        sql = "CREATE TABLE [{new_table}] AS SELECT * FROM [{table}];".format(
            new_table = name_new,
            table = self.name,
        )
        self.db.execute(sql)
    return self.db[name_new]

```

I like the idea of this as a feature - design could look like this:

db["my_table"].duplicate("new_table")

Then for the CLI tool:

sqlite-utils duplicate data.db my_table new_table

Additional features that might be useful:

• Duplicate across connection aliases - so you can copy a table to another database using the duplicate method or command
• Ability to execute an arbitrary SQL query and save the results to a new table - basically a wrapper around CREATE TABLE t AS SELECT ..., again with alias support for copying to another database