Better SQL prepared statements (#2474)

The system used to be of complexity O(n^2). Essentially two for loops running per every argument. Which ended up being surprisingly slow (there were instances where I saw the argument parser as using quite a lot of CPU time).

This replaces it with a more linear algorithm. It's somewhere near O(n) where n is the length of the unparsed query. Which is more stable and faaaster. This comes with two changes, however:

Parameters inside the query now have to be delimited from both sides with : (colons). The alternative to this would be to use something like $n or just assume that space marks the end of a marker. Only the former is workable, the latter would break a few queries already.
Arguments in the argument array no longer have to be prefixed by : (colons). So, while in the query you would write :thing:, you'd initialize the array of args as: list("thing" = somevar). It could be made to work without it, but eh, I think this is fine.
Argument validation is slightly weaker. What I mean by this is that with the old system, unused keys would result in an error. This is no longer a thing. Missing keys will still result in an error, however.
One more improvement: double delimiting removes an edge case where if key A partially covers key B, depending on the order, key A would mangle key B.
Updated and tested all queries that I could find. So this should be good.
This commit is contained in:
skull132
2017-05-29 21:17:41 +03:00
committed by GitHub
parent b88d6aaadb
commit a3ec0cf45d
36 changed files with 366 additions and 333 deletions
@@ -31,7 +31,7 @@
"ss13_characters" = list("vars" = list("home_system", "citizenship", "faction", "religion"), "args" = list("id")))
/datum/category_item/player_setup_item/general/background/gather_load_parameters()
return list(":id" = pref.current_character, ":char_id" = pref.current_character)
return list("id" = pref.current_character, "char_id" = pref.current_character)
/datum/category_item/player_setup_item/general/background/gather_save_query()
return list("ss13_characters_flavour" = list("records_employment",
@@ -41,16 +41,16 @@
"ss13_characters" = list("home_system", "citizenship", "faction", "religion", "id" = 1, "ckey" = 1))
/datum/category_item/player_setup_item/general/background/gather_save_parameters()
return list(":records_employment" = pref.gen_record,
":records_medical" = pref.med_record,
":records_security" = pref.sec_record,
":char_id" = pref.current_character,
":home_system" = pref.home_system,
":citizenship" = pref.citizenship,
":faction" = pref.faction,
":religion" = pref.religion,
":id" = pref.current_character,
":ckey" = pref.client.ckey)
return list("records_employment" = pref.gen_record,
"records_medical" = pref.med_record,
"records_security" = pref.sec_record,
"char_id" = pref.current_character,
"home_system" = pref.home_system,
"citizenship" = pref.citizenship,
"faction" = pref.faction,
"religion" = pref.religion,
"id" = pref.current_character,
"ckey" = pref.client.ckey)
/datum/category_item/player_setup_item/general/background/sanitize_character()
if(!pref.home_system)