[Maria-developers] MySQL Bug 59449 - Accepted by MariaDB?
I just submitted a patch to a MySQL bug that I am also experiencing. I would like to see it accepted into the wider community (MySQL, MariaDB, Percona, etc). Please let me know what I need to do so that this patch could also be accepted into your project. The bug is here: http://bugs.mysql.com/bug.php?id=59449 The "[11 Jun 3:16] Jeremy Thomerson" comment will be the most useful. Please CC me on any replies to this thread because I am not subscribed to this mailing list. Best Regards, Jeremy Thomerson
Hi, Jeremy! On Jun 10, Jeremy Thomerson wrote:
You don't need to do anything. At least not yet. We still merge with upstream from time to time, so when this bug will be fixed in MySQL, we'll get it too. But if Oracle will refuse to fix this bug, we will look at your patch, certainly. Regards, Sergei
Hi!
"Sergei" == Sergei Golubchik <serg@askmonty.org> writes:
Sergei> Hi, Jeremy! Sergei> On Jun 10, Jeremy Thomerson wrote:
Sergei> You don't need to do anything. At least not yet. Sergei> We still merge with upstream from time to time, so when this bug will be Sergei> fixed in MySQL, we'll get it too. Sergei> But if Oracle will refuse to fix this bug, we will look at your patch, Sergei> certainly. To ensure we don't forget about this, if you are not sure that Oracle has fixed the bug within one month, ping us and we will look at adding this into MariaDB at once. Regards, Monty
Monty, et al... On Mon, Jun 13, 2011 at 9:36 AM, Michael Widenius <monty@askmonty.org>wrote:
Thanks a bunch! I was away a lot in July and August and didn't get to follow up on this. Looking at the original bug report, I have seen absolutely no activity. I'm not even sure why they have not touched / accepted it. If anyone here knows a way to get it into one (or both) projects, I'd appreciate any help you can offer. Thanks! Jeremy Thomerson
Hi!
"Jeremy" == Jeremy Thomerson <jeremy@thomersonfamily.com> writes:
Jeremy> Monty, et al... Jeremy> On Mon, Jun 13, 2011 at 9:36 AM, Michael Widenius <monty@askmonty.org>wrote:
Sergei> But if Oracle will refuse to fix this bug, we will look at your
Jeremy> Thanks a bunch! I was away a lot in July and August and didn't get to Jeremy> follow up on this. Looking at the original bug report, I have seen Jeremy> absolutely no activity. I'm not even sure why they have not touched / Jeremy> accepted it. If anyone here knows a way to get it into one (or both) Jeremy> projects, I'd appreciate any help you can offer. The patch you suggested was: === modified file 'sql/sql_base.cc' --- sql/sql_base.cc 2011-04-12 10:59:59 +0000 +++ sql/sql_base.cc 2011-06-10 20:11:52 +0000 @@ -6975,6 +6975,28 @@ *counter= i; *resolution= RESOLVED_IGNORING_ALIAS; break; + } + else if (find->type() == Item::FUNC_ITEM && ((Item_func*) find)->functype() == Item_func::COLLATE_FUNC && ((Item_func*) find)->arg_count == 2) + { + /* + If someone uses "ORDER BY column_name COLLATE utf8_spanish_ci", it is a function + that we are trying to find, and not a real column. Bug #59449 exposes that this + failed when column_name is actually referring to the name of an alias, whether + that alias is for a real column or for a function result (such as coalesce). This + block of code finds the real item, which is the "column" referred to by the + collation function for this scenario. + */ + Item *collated_column = ((Item_func*) find)->arguments()[0]; + int is_alias = item->type() == Item::FUNC_ITEM || + ((item->type() == Item::FIELD_ITEM || item->type() == Item::REF_ITEM) && + my_strcasecmp(system_charset_info, ((Item_ident*) item)->field_name, item->name)); + if (is_alias && collated_column->name && item->name && !my_strcasecmp(system_charset_info, item->name, collated_column->name)) + { + found = &collated_column; + *counter = i; + *resolution = RESOLVED_BEHIND_ALIAS; + break; + } } } else if (table_name && item->type() == Item::REF_ITEM && What I don't like with the patch is that we make COLLATE a special case. I think that all usage of alias names in ORDER BY should be treated the same. In other words: ORDER BY LanguageName ORDER BY LanguageName COLLATE utf8_spanish_ci ORDER BY concat(LanguageName,"aa") should all use either the column or the alias in the same manner. As we normally prefer alias for a column name in the ORDER BY, I think we should fix this so that we always prefer the alias name in all ORDER BY context. The other option would be to give an error in this case as it's not clear what the user wants. This is hower likely to break many old applictions. After talking with Sergei, he concluded: "yes, I believe now that according to the SQL:2003 (ISO/IEC 9075-2:2003, part 2 (foundations), 14.1 <declare cursor>, Syntax Rules, item 18) aliases from the select list take precedence over column names from the table" The standard is very vague in the area, but it seams to support the idea that alias'es should resolve first). This means that we should fix things to always first prefer alias. The fix in this case needs to be done in item::fix_fields() and not in sql_base.cc I will ask Timour to see if he can provide a fix for this. (As he knows the fix_fields code quite well and he needs something to bite into now when he is back from his vacation). Timour, can you handle this? Regards, Monty
participants (3)
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Jeremy Thomerson -
Michael Widenius -
Sergei Golubchik