From experience I'll say one thing that Polars doesn't have great interfacing with is doing things like string concatenation, like taking multiple columns and combining them in with static string text in complex ways to create new columns.

Pandas has a really simple ability to just define a new column with

`df['col_a'] + "text" + df[col_b']` where "text" can be any string text inbetween your column values from col_a and col_b

If i remember correctly while you can do pl.col("col_a") + pl.("col_b") for plain concatenation, you can't mix in static text strings like you can with pandas and I haven't found really elegant ways to do that personally. Whereas I've found polars doesn't have as simple of a way to do that. You can choose to add one separator and make that anything you want, but only one separator and only inbetween the two values (so no suffixes or prefixes for example).

That being said, I hate everything to do with the pandas API (especially with its indexing system) and really prefer the more polars API for anyone coming from a SQL or database background. Pandas really shows its sort of academia background rather than a data engineering origin.

I'm not sure what you tried. Is this not what you want?

    >>> df = pl.DataFrame({"x": ["a", "b", "c"], "y": ["d", "e", "f"]})
    >>> df.with_columns(new=pl.col.x + " text " + pl.col.y)
    shape: (3, 3)
    ┌─────┬─────┬──────────┐
    │ x   ┆ y   ┆ new      │
    │ --- ┆ --- ┆ ---      │
    │ str ┆ str ┆ str      │
    ╞═════╪═════╪══════════╡
    │ a   ┆ d   ┆ a text d │
    │ b   ┆ e   ┆ b text e │
    │ c   ┆ f   ┆ c text f │
    └─────┴─────┴──────────┘