From 1a5a5c7edb8697c93f8bababbafa80245378dd7e Mon Sep 17 00:00:00 2001 From: Habeas Codice Date: Thu, 13 Nov 2014 12:21:58 -0800 Subject: PostgreSQL support initial commit There were 11 main types of changes: - UPDATE's and DELETE's sometimes had LIMIT 1 at the end of them. This is not only non-compliant but it would certainly not do what whoever wrote it thought it would. It is likely this mistake was just copied from Friendica. All of these instances, the LIMIT 1 was simply removed. - Bitwise operations (and even some non-zero int checks) erroneously rely on MySQL implicit integer-boolean conversion in the WHERE clauses. This is non-compliant (and bad programming practice to boot). Proper explicit boolean conversions were added. New queries should use proper conventions. - MySQL has a different operator for bitwise XOR than postgres. Rather than add yet another dba_ func, I converted them to "& ~" ("AND NOT") when turning off, and "|" ("OR") when turning on. There were no true toggles (XOR). New queries should refrain from using XOR when not necessary. - There are several fields which the schema has marked as NOT NULL, but the inserts don't specify them. The reason this works is because mysql totally ignores the constraint and adds an empty text default automatically. Again, non-compliant, obviously. In these cases a default of empty text was added. - Several statements rely on a non-standard MySQL feature (http://dev.mysql.com/doc/refman/5.5/en/group-by-handling.html). These queries can all be rewritten to be standards compliant. Interestingly enough, the newly rewritten standards compliant queries run a zillion times faster, even on MySQL. - A couple of function/operator name translations were needed (RAND/RANDOM, GROUP_CONCAT/STRING_AGG, UTC_NOW, REGEXP/~, ^/#) -- assist functions added in the dba_ - INTERVALs: postgres requires quotes around the value, mysql requires that there are not quotes around the value -- assist functions added in the dba_ - NULL_DATE's -- Postgres does not allow the invalid date '0000-00-00 00:00:00' (there is no such thing as year 0 or month 0 or day 0). We use '0001-01-01 00:00:00' for postgres. Conversions are handled in Zot/item packets automagically by quoting all dates with dbescdate(). - char(##) specifications in the schema creates fields with blank spaces that aren't trimmed in the code. MySQL apparently treats char(##) as varchar(##), again, non-compliant. Since postgres works better with text fields anyway, this ball of bugs was simply side-stepped by using 'text' datatype for all text fields in the postgres schema. varchar was used in a couple of places where it actually seemed appropriate (size constraint), but without rigorously vetting that all of the PHP code actually validates data, new bugs might come out from under the rug. - postgres doesn't store nul bytes and a few other non-printables in text fields, even when quoted. bytea fields were used when storing binary data (photo.data, attach.data). A new dbescbin() function was added to handle this transparently. - postgres does not support LIMIT #,# syntax. All databases support LIMIT # OFFSET # syntax. Statements were updated to be standard. These changes require corresponding changes in the coding standards. Please review those before adding any code going forward. Still on my TODO list: - remove quotes from non-reserved identifiers and make reserved identifiers use dba func for quoting - Rewrite search queries for better results (both MySQL and Postgres) --- include/message.php | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include/message.php') diff --git a/include/message.php b/include/message.php index b063530d6..49278f273 100644 --- a/include/message.php +++ b/include/message.php @@ -243,7 +243,7 @@ function private_messages_list($uid, $mailbox = '', $start = 0, $numitems = 0) { $limit = ''; if($numitems) - $limit = " LIMIT " . intval($start) . ", " . intval($numitems); + $limit = " LIMIT " . intval($numitems) . " OFFSET " . intval($start); if($mailbox !== '') { $x = q("select channel_hash from channel where channel_id = %d limit 1", @@ -332,7 +332,7 @@ function private_messages_fetch_message($channel_id, $messageitem_id, $updatesee } if($updateseen) { - $r = q("UPDATE `mail` SET mail_flags = (mail_flags ^ %d) where not (mail_flags & %d) and id = %d AND channel_id = %d", + $r = q("UPDATE `mail` SET mail_flags = (mail_flags | %d) where not (mail_flags & %d)>0 and id = %d AND channel_id = %d", intval(MAIL_SEEN), intval(MAIL_SEEN), dbesc($messageitem_id), @@ -363,7 +363,7 @@ function private_messages_drop($channel_id, $messageitem_id, $drop_conversation } } else { - $r = q("DELETE FROM mail WHERE id = %d AND channel_id = %d LIMIT 1", + $r = q("DELETE FROM mail WHERE id = %d AND channel_id = %d", intval($messageitem_id), intval($channel_id) ); @@ -421,7 +421,7 @@ function private_messages_fetch_conversation($channel_id, $messageitem_id, $upda if($updateseen) { - $r = q("UPDATE `mail` SET mail_flags = (mail_flags ^ %d) where not (mail_flags & %d) and parent_mid = '%s' AND channel_id = %d", + $r = q("UPDATE `mail` SET mail_flags = (mail_flags | %d) where not (mail_flags & %d)>0 and parent_mid = '%s' AND channel_id = %d", intval(MAIL_SEEN), intval(MAIL_SEEN), dbesc($r[0]['parent_mid']), -- cgit v1.2.3