The irony

[Tim Chase]

(interspersing letters to name your examples)

On 2016-05-10 14:03, DFS wrote:

A (nope)
> -----------------------------------
> sSQL =  "line 1\n"
> sSQL += "line 2\n"
> sSQL += "line 3"

B (see below)
> -----------------------------------
> sSQL = ("line 1\n"
>          "line 2\n"
>          "line 3")

C (see below)
> -----------------------------------
> sSQL = "\n".join([
>           "line 1",
>           "line 2",
>           "line 3",
>         ])

D (almost)
> -----------------------------------
> sSQL =  """line 1
> line 2
> line 3"""

E (almost)
> -----------------------------------
> sSQL = """\
> line 1
> line 2
> line 3"""

F (not bad)
> -----------------------------------
> sSQL = "line 1\n" \
>         "line 2\n" \
>         "line 3"

> Which is the "one obvious way" to do it?

Readability is one of Python's key strengths.  I find my choice(s)
influenced by ease-of-reading and ease-of-editing (along with its
friend, ease-of-reading-diffs).

As leading indentation doesn't usually matter in SQL, I tend to just
use triple-quoted strings for all my SQL, formatting so it looks like
good SQL:

  sql = """
    SELECT
      a.foo,
      b.bar
    FROM tblA a
      INNER JOIN tblB b
      ON a.id = b.a_id
    WHERE
      a.osteopathy > b.saturation
    ORDER BY
      b.monkey_balloon
    """

This does mean that there's a superfluous newline at the beginning &
end of the string and unneeded indentation for each line. But SQL
doesn't care, and if it had any noticeable performance issue (ooh, a
couple dozen extra bytes getting sent over the wire), it could be
post-processed to a clean one-liner.

That said, there are cases where the leading indentation does matter
to you, then I tend to use your "C" example for code executed once,
or a modification of B for code in loops:

  sql = (
    "line1\n"
    "line2\n"
    "line3"
    )

(the difference being the newline after the open-paren to align all
the strings' starting offset)

If the redundancy of the "\n" characters became sufficiently
annoying, I'd define a constant (evaluated once, not in a loop) using
the "\n".join(...) method.

Seek the code that reads best for you and meets your needs.

-tkc