Pythonic way to create a long multi

I have a very long query. I would like to split it in several lines in Python. A way to do it in JavaScript would be using several sentences and joining them with a + operator (I know, maybe it's not the most efficient way to do it, but I'm not really concerned about performance in this stage, just code readability). Example:

var long_string = 'some text not important. just garbage to' +
                  'illustrate my example';

I tried doing something similar in Python, but it didn't work, so I used to split the long string. However, I'm not sure if this is the only/best/pythonicest way of doing it. It looks awkward. Actual code:

query = 'SELECT action.descr as "action", '
    'role.id as role_id,'
    'role.descr as role'
    'FROM '
    'public.role_action_def,'
    'public.role,'
    'public.record_def, '
    'public.action'
    'WHERE role.id = role_action_def.role_id AND'
    'record_def.id = role_action_def.def_id AND'
    'action.id = role_action_def.action_id AND'
    'role_action_def.account_id = ' + account_id + ' AND'
    'record_def.account_id=' + account_id + ' AND'
    'def_id=' + def_id

Are you talking about multi-line strings? Easy, use triple quotes to start and end them.

s = """ this is a very
        long string if I had the
        energy to type more and more ..."""

You can use single quotes too (3 of them of course at start and end) and treat the resulting string s just like any other string.

NOTE : Just as with any string, anything between the starting and ending quotes becomes part of the string, so this example has a leading blank (as pointed out by @root45). This string will also contain both blanks and newlines.

Ie,:

' this is a veryn        long string if I had then        energy to type more and more ...'

Finally, one can also construct long lines in Python like this:

 s = ("this is a very"
      "long string too"
      "for sure ..."
     )

which will not include any extra blanks or newlines (this is a deliberate example showing what the effect of skipping blanks will result in):

'this is a verylong string toofor sure ...'

No commas required, simply place the strings to be joined together into a pair of parenthesis and be sure to account for any needed blanks and newlines.


If you don't want a multiline string but just have a long single line string, you can use parentheses, just make sure you don't include commas between the string segments, then it will be a tuple.

query = ('SELECT   action.descr as "action", '
         'role.id as role_id,'
         'role.descr as role'
         ' FROM '
         'public.role_action_def,'
         'public.role,'
         'public.record_def, '
         'public.action'
         ' WHERE role.id = role_action_def.role_id AND'
         ' record_def.id = role_action_def.def_id AND'
         ' action.id = role_action_def.action_id AND'
         ' role_action_def.account_id = '+account_id+' AND'
         ' record_def.account_id='+account_id+' AND'
         ' def_id='+def_id)

In a SQL statement like what you're constructing, multiline strings would also be fine. But if the extra whitespace a multiline string would contain would be a problem, then this would be a good way to achieve what you want.


Breaking lines by works for me. Here is an example:

longStr = "This is a very long string " 
        "that I wrote to help somebody " 
        "who had a question about " 
        "writing long strings in Python"
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