Make the GROUP_CONCAT aggregate function not repeat values (closes #3223975)
Work on sets instead of arrays, so if the same value appears twice it's
not repeated in the concatenated output.
This patch handles the postgresql and sqlite backends, mysql is left
alone at this point (seems doable, but I don't have time or motivation
to fix and test it).
[MESSAGES CONTROL]
disable-msg = C0301
[VARIABLES]
# Enable / disable this checker
enable-variables = yes
additional-builtins = _, display_name
[BASIC]
required-attributes=
attr-rgx = (w|[a-z_][a-z0-9_]{2,30})
variable-rgx = (w|[a-z_][a-z0-9_]{2,30})$
argument-rgx = (w|[a-z_][a-z0-9_]{2,30})$
[TYPECHECK]
generated-members=debug,info,notice,warning,error,critical,exception