Pythonic way to create a long multi-line string

Question

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 +<

Answer 1

Combining the ideas from:

Levon or Jesse, Faheel and ddrscott

with my formatting suggestion, you could write your query as:

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
         )

 vars = (account_id, account_id, def_id)     # a tuple of the query variables
 cursor.execute(query, vars)                 # using Python's sqlite3 module

or like:

vars = []
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 = '
                 vars.append(account_id) or '?'
             ' AND'
             ' record_def.account_id = '
                 vars.append(account_id) or '?'
             ' AND'
             ' def_id = '
                 vars.append(def_id) or '?'
         )

 cursor.execute(query, tuple(vars))  # using Python's sqlite3 module

Which could be interesting together with 'IN' and 'vars.extend(options) or n_options(len(options))', where:

def n_options(count):
    return '(' + ','.join(count*'?') + ')'

Or with the hint from darkfeline, that you might still make mistakes with those leading spaces and separators and also with named placeholders:

SPACE_SEP = ' '
COMMA_SEP = ', '
AND_SEP   = ' AND '

query = SPACE_SEP.join((
    'SELECT',
        COMMA_SEP.join((
        'action.descr as "action"',
        'role.id as role_id',
        'role.descr as role',
        )),
    'FROM',
        COMMA_SEP.join((
        'public.role_action_def',
        'public.role',
        'public.record_def',
        'public.action',
        )),
    'WHERE',
        AND_SEP.join((
        'role.id = role_action_def.role_id',
        'record_def.id = role_action_def.def_id',
        'action.id = role_action_def.action_id',
        'role_action_def.account_id = :account_id',
        'record_def.account_id = :account_id',
        'def_id = :def_id',
        )),
    ))

vars = {'account_id':account_id,'def_id':def_id}  # a dictionary of the query variables
cursor.execute(query, vars)                       # using Python's sqlite3 module

See documentation of Cursor.execute-function.

"This is the [most pythonic] way!" - ...