From fjoe@iclub.nsu.ru Tue Jan 23 03:38:45 2001 Received: from mx.nsu.ru (root@mx.nsu.ru [193.124.215.71]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id DAA14458 for ; Tue, 23 Jan 2001 03:38:24 -0500 (EST) Received: from iclub.nsu.ru (root@iclub.nsu.ru [193.124.222.66]) by mx.nsu.ru (8.9.1/8.9.0) with ESMTP id OAA29153; Tue, 23 Jan 2001 14:31:27 +0600 (NOVT) Received: from localhost (fjoe@localhost) by iclub.nsu.ru (8.11.1/8.11.1) with ESMTP id f0N8VOr15273; Tue, 23 Jan 2001 14:31:25 +0600 (NS) (envelope-from fjoe@iclub.nsu.ru) Date: Tue, 23 Jan 2001 14:31:24 +0600 (NS) From: Max Khon To: Bruce Momjian cc: PostgreSQL-development Subject: Re: [HACKERS] Bug in FOREIGN KEY In-Reply-To: <200101230416.XAA04293@candle.pha.pa.us> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Status: RO hi, there! On Mon, 22 Jan 2001, Bruce Momjian wrote: > > > This problem with foreign keys has been reported to me, and I have confirmed > > the bug exists in current sources. The DELETE should succeed: > > > > --------------------------------------------------------------------------- > > > > CREATE TABLE primarytest2 ( > > col1 INTEGER, > > col2 INTEGER, > > PRIMARY KEY(col1, col2) > > ); > > > > CREATE TABLE foreigntest2 (col3 INTEGER, > > col4 INTEGER, > > FOREIGN KEY (col3, col4) REFERENCES primarytest2 > > ); > > test=> BEGIN; > > BEGIN > > test=> INSERT INTO primarytest2 VALUES (5,5); > > INSERT 27618 1 > > test=> DELETE FROM primarytest2 WHERE col1 = 5 AND col2 = 5; > > ERROR: triggered data change violation on relation "primarytest2" I have another (slightly different) example: --- cut here --- test=> CREATE TABLE pr(obj_id int PRIMARY KEY); NOTICE: CREATE TABLE/PRIMARY KEY will create implicit index 'pr_pkey' for table 'pr' CREATE test=> CREATE TABLE fr(obj_id int REFERENCES pr ON DELETE CASCADE); NOTICE: CREATE TABLE will create implicit trigger(s) for FOREIGN KEY check(s) CREATE test=> BEGIN; BEGIN test=> INSERT INTO pr (obj_id) VALUES (1); INSERT 200539 1 test=> INSERT INTO fr (obj_id) SELECT obj_id FROM pr; INSERT 200540 1 test=> DELETE FROM fr; ERROR: triggered data change violation on relation "fr" test=> --- cut here --- we are running postgresql 7.1 beta3 /fjoe From sszabo@megazone23.bigpanda.com Tue Jan 23 13:41:55 2001 Received: from megazone23.bigpanda.com (rfx-64-6-210-138.users.reflexcom.com [64.6.210.138]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id NAA19924 for ; Tue, 23 Jan 2001 13:41:54 -0500 (EST) Received: from localhost (sszabo@localhost) by megazone23.bigpanda.com (8.11.1/8.11.1) with ESMTP id f0NIfLa41018; Tue, 23 Jan 2001 10:41:21 -0800 (PST) Date: Tue, 23 Jan 2001 10:41:21 -0800 (PST) From: Stephan Szabo To: Bruce Momjian cc: Jan Wieck , Peter Eisentraut , PostgreSQL-development Subject: Re: [HACKERS] Bug in FOREIGN KEY In-Reply-To: <200101230417.XAA04332@candle.pha.pa.us> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Status: RO > > Think I misinterpreted the SQL3 specs WR to this detail. The > > checks must be made per statement, not at the transaction > > level. I'll try to fix it, but we need to define what will > > happen with referential actions in the case of conflicting > > actions on the same key - there are some possible conflicts: > > > > 1. DEFERRED ON DELETE NO ACTION or RESTRICT > > > > Do the referencing rows reference to the new PK row with > > the same key now, or is this still a constraint > > violation? I would say it's not, because the constraint > > condition is satisfied at the end of the transaction. How > > do other databases behave? > > > > 2. DEFERRED ON DELETE CASCADE, SET NULL or SET DEFAULT > > > > Again I'd say that the action should be suppressed > > because a matching PK row is present at transaction end - > > it's not the same old row, but the constraint itself is > > still satisfied. I'm not actually sure on the cascade, set null and set default. The way they are written seems to imply to me that it's based on the state of the database before/after the command in question as opposed to the deferred state of the database because of the stuff about updating the state of partially matching rows immediately after the delete/update of the row which wouldn't really make sense when deferred. Does anyone know what other systems do with a case something like this all in a transaction: create table a (a int primary key); create table b (b int references a match full on update cascade on delete cascade deferrable initially deferred); insert into a values (1); insert into a values (2); insert into b values (1); delete from a where a=1; select * from b; commit; From pgsql-hackers-owner+M3901@postgresql.org Fri Jan 26 17:00:24 2001 Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id RAA10576 for ; Fri, 26 Jan 2001 17:00:24 -0500 (EST) Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id f0QLtVq53019; Fri, 26 Jan 2001 16:55:31 -0500 (EST) (envelope-from pgsql-hackers-owner+M3901@postgresql.org) Received: from smtp1b.mail.yahoo.com (smtp3.mail.yahoo.com [128.11.68.135]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id f0QLqmq52691 for ; Fri, 26 Jan 2001 16:52:48 -0500 (EST) (envelope-from janwieck@yahoo.com) Received: from j13.us.greatbridge.com (HELO jupiter.greatbridge.com) (216.54.52.153) by smtp.mail.vip.suc.yahoo.com with SMTP; 26 Jan 2001 22:49:57 -0000 X-Apparently-From: Received: (from janwieck@localhost) by jupiter.greatbridge.com (8.9.3/8.9.3) id RAA04701; Fri, 26 Jan 2001 17:02:32 -0500 From: Jan Wieck Message-Id: <200101262202.RAA04701@jupiter.greatbridge.com> Subject: Re: [HACKERS] Bug in FOREIGN KEY In-Reply-To: <200101262110.QAA06902@candle.pha.pa.us> from Bruce Momjian at "Jan 26, 2001 04:10:22 pm" To: Bruce Momjian Date: Fri, 26 Jan 2001 17:02:32 -0500 (EST) CC: Jan Wieck , Peter Eisentraut , PostgreSQL-development X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org Status: RO Bruce Momjian wrote: > Here is another bug: > > test=> begin; > BEGIN > test=> INSERT INTO primarytest2 VALUES (5,5); > INSERT 18757 1 > test=> UPDATE primarytest2 SET col2=1 WHERE col1 = 5 AND col2 = 5; > ERROR: deferredTriggerGetPreviousEvent: event for tuple (0,10) not > found Schema? Jan -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== JanWieck@Yahoo.com # _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com From pgsql-hackers-owner+M3864@postgresql.org Fri Jan 26 10:07:36 2001 Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id KAA17732 for ; Fri, 26 Jan 2001 10:07:35 -0500 (EST) Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id f0QF3lq12782; Fri, 26 Jan 2001 10:03:47 -0500 (EST) (envelope-from pgsql-hackers-owner+M3864@postgresql.org) Received: from mailout00.sul.t-online.com (mailout00.sul.t-online.com [194.25.134.16]) by mail.postgresql.org (8.11.1/8.11.1) with ESMTP id f0QF0Yq12614 for ; Fri, 26 Jan 2001 10:00:34 -0500 (EST) (envelope-from peter_e@gmx.net) Received: from fwd01.sul.t-online.com by mailout00.sul.t-online.com with smtp id 14MALp-0006Im-00; Fri, 26 Jan 2001 15:59:45 +0100 Received: from peter.localdomain (520083510237-0001@[212.185.245.73]) by fmrl01.sul.t-online.com with esmtp id 14MALQ-1Z0gkaC; Fri, 26 Jan 2001 15:59:20 +0100 Date: Fri, 26 Jan 2001 16:07:27 +0100 (CET) From: Peter Eisentraut To: Hiroshi Inoue cc: Bruce Momjian , PostgreSQL-development Subject: Re: [HACKERS] Open 7.1 items In-Reply-To: <3A70FA87.933B3D51@tpf.co.jp> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Sender: 520083510237-0001@t-dialin.net Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org Status: RO Hiroshi Inoue writes: > What does this item mean ? > Is it the following ? > > begin; > insert into pk (id) values (1); > update(delete from) pk where id=1; > ERROR: triggered data change violation on relation pk" > > If so, isn't it a simple bug ? Depends on the definition of "bug". It's not spec compliant and it's not documented and it's annoying. But it's been like this for a year and the issue is well known and can normally be avoided. It looks like a documentation to-do to me. -- Peter Eisentraut peter_e@gmx.net http://yi.org/peter-e/ From pgsql-hackers-owner+M3876@postgresql.org Fri Jan 26 13:07:10 2001 Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id NAA26086 for ; Fri, 26 Jan 2001 13:07:09 -0500 (EST) Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id f0QI4Vq30248; Fri, 26 Jan 2001 13:04:31 -0500 (EST) (envelope-from pgsql-hackers-owner+M3876@postgresql.org) Received: from sectorbase2.sectorbase.com ([208.48.122.131]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id f0QI3Aq30098 for ; Fri, 26 Jan 2001 13:03:11 -0500 (EST) (envelope-from vmikheev@SECTORBASE.COM) Received: by sectorbase2.sectorbase.com with Internet Mail Service (5.5.2653.19) id ; Fri, 26 Jan 2001 09:41:23 -0800 Message-ID: <8F4C99C66D04D4118F580090272A7A234D32C1@sectorbase1.sectorbase.com> From: "Mikheev, Vadim" To: "'Jan Wieck'" , PostgreSQL HACKERS , Bruce Momjian Subject: RE: [HACKERS] Open 7.1 items Date: Fri, 26 Jan 2001 10:02:59 -0800 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org Status: RO > > FOREIGN KEY INSERT & UPDATE/DELETE in transaction "change violation" > > A well known issue, and I've asked multiple times how exactly > we want to define the behaviour for deferred constraints. Do > foreign keys reference just to a key value and are happy with > it's existance, or do they refer to a particular row? I think first. The last is closer to OODBMS world, not to [O]RDBMS one. > Consider you have a deferred "ON DELETE CASCADE" constraint > and do a DELETE, INSERT of a PK. Do the FK rows need to be > deleted or not? Good example. I think FK should not be deleted. If someone really want to delete "old" FK then he can do DELETE PK; SET CONSTRAINT ... IMMEDIATE; -- FK need to be deleted here INSERT PK; > Consider you have a deferred "ON DELETE RESTRICT" and "ON > UPDATE CASCADE" constraint. If you DELETE PK1 and UPDATE PK2 > to PK1, the FK2 rows need to follow, but does PK2 inherit all > FK1 rows now so it's the master of both groups? Yes. Again one can use SET CONSTRAINT to achieve desirable results. It seems that SET CONSTRAINT was designed for these purposes - ie for better flexibility. Though, it would be better to look how other DBes handle all these cases -:) Vadim From janwieck@yahoo.com Fri Jan 26 12:20:27 2001 Received: from smtp6.mail.yahoo.com (smtp6.mail.yahoo.com [128.11.69.103]) by candle.pha.pa.us (8.9.0/8.9.0) with SMTP id MAA22158 for ; Fri, 26 Jan 2001 12:20:27 -0500 (EST) Received: from j13.us.greatbridge.com (HELO jupiter.greatbridge.com) (216.54.52.153) by smtp.mail.vip.suc.yahoo.com with SMTP; 26 Jan 2001 17:20:26 -0000 X-Apparently-From: Received: (from janwieck@localhost) by jupiter.greatbridge.com (8.9.3/8.9.3) id MAA03196; Fri, 26 Jan 2001 12:30:05 -0500 From: Jan Wieck Message-Id: <200101261730.MAA03196@jupiter.greatbridge.com> Subject: Re: [HACKERS] Open 7.1 items To: PostgreSQL HACKERS , Bruce Momjian Date: Fri, 26 Jan 2001 12:30:05 -0500 (EST) X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Status: RO Bruce Momjian wrote: > Here are my open 7.1 items. Thanks for shrinking the list so far. > > --------------------------------------------------------------------------- > > FreeBSD locale bug > Reorder INSERT firing in rules I don't recall why this is wanted. AFAIK there's no reason NOT to do so, except for the actual state of beeing far too close to a release candidate. > Philip Warner UPDATE crash > JDBC LargeObject short read return value missing > SELECT cash_out(1) crashes all backends > LAZY VACUUM > FOREIGN KEY INSERT & UPDATE/DELETE in transaction "change violation" A well known issue, and I've asked multiple times how exactly we want to define the behaviour for deferred constraints. Do foreign keys reference just to a key value and are happy with it's existance, or do they refer to a particular row? Consider you have a deferred "ON DELETE CASCADE" constraint and do a DELETE, INSERT of a PK. Do the FK rows need to be deleted or not? Consider you have a deferred "ON DELETE RESTRICT" and "ON UPDATE CASCADE" constraint. If you DELETE PK1 and UPDATE PK2 to PK1, the FK2 rows need to follow, but does PK2 inherit all FK1 rows now so it's the master of both groups? These are only two possible combinations. There are many to think of. As said, I've asked before, but noone voted yet. Move the item to 7.2 anyway, because changing this behaviour would require massive changes in the trigger queue *and* the generic RI triggers, which cannot be tested enough any more. Jan > Usernames limited in length > Does pg_dump preserve COMMENTs? > Failure of nested cursors in JDBC > JDBC setMaxRows() is global variable affecting other objects > Does JDBC Makefile need current dir? > Fix for pg_dump of bad system tables > Steve Howe failure query with rules > ODBC/JDBC not disconnecting properly? > Magnus Hagander ODBC issues? > Merge MySQL/PgSQL translation scripts > Fix ipcclean on Linux > Merge global and template BKI files? > > > -- > Bruce Momjian | http://candle.pha.pa.us > pgman@candle.pha.pa.us | (610) 853-3000 > + If your life is a hard drive, | 830 Blythe Avenue > + Christ can be your backup. | Drexel Hill, Pennsylvania 19026 > -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== JanWieck@Yahoo.com # _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com From pgsql-general-owner+M590@postgresql.org Tue Nov 14 16:30:40 2000 Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by candle.pha.pa.us (8.9.0/8.9.0) with ESMTP id RAA22313 for ; Tue, 14 Nov 2000 17:30:39 -0500 (EST) Received: from mail.postgresql.org (webmail.postgresql.org [216.126.85.28]) by mail.postgresql.org (8.11.1/8.11.1) with SMTP id eAEMSJs66979; Tue, 14 Nov 2000 17:28:21 -0500 (EST) (envelope-from pgsql-general-owner+M590@postgresql.org) Received: from megazone23.bigpanda.com (138.210.6.64.reflexcom.com [64.6.210.138]) by mail.postgresql.org (8.11.1/8.11.1) with ESMTP id eAEMREs66800 for ; Tue, 14 Nov 2000 17:27:14 -0500 (EST) (envelope-from sszabo@megazone23.bigpanda.com) Received: from localhost (sszabo@localhost) by megazone23.bigpanda.com (8.11.1/8.11.0) with ESMTP id eAEMPpH69059; Tue, 14 Nov 2000 14:25:51 -0800 (PST) Date: Tue, 14 Nov 2000 14:25:51 -0800 (PST) From: Stephan Szabo To: "Beth K. Gatewood" cc: pgsql-general@postgresql.org Subject: Re: [GENERAL] a request for some experienced input..... In-Reply-To: <3A11ACA1.E5D847DD@mbt.washington.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Sender: pgsql-general-owner@postgresql.org Status: OR On Tue, 14 Nov 2000, Beth K. Gatewood wrote: > > > > Stephan- > > Thank you so much for taking the effort to answer this these questions. You > help is truly appreciated.... > > I just have a few points for clarification. > > > > > MATCH PARTIAL is a specific match type which describes which rows are > > considered matching rows for purposes of meeting or failing the > > constraint. (In match partial, a fktable (NULL, 2) would match a pk > > table (1,2) as well as a pk table (2,2). It's different from match > > full in which case (NULL,2) would be invalid or match unspecified > > in which case it would match due to the existance of the NULL in any > > case). There are some bizarre implementation details involved with > > it and it's different from the others in ways that make it difficult. > > It's in my list of things to do, but I haven't come up with an acceptable > > mechanism in my head yet. > > Does this mean, currently that I can not have foreign keys with null values? Not exactly... Match full = In FK row, all columns must be NULL or the value of each column must not be null and there is a row in the PK table where each referencing column equals the corresponding referenced column. Unspecified = In FK row, at least one column must be NULL or each referencing column shall be equal to the corresponding referenced column in some row of the referenced table Match partial is similar to match full except we ignore the null columns for purposes of the each referencing column equals bit. For example: PK Table Key values: (1,2), (1,3), (3,3) Attempted FK Table Key values: (1,2), (1,NULL), (5,NULL), (NULL, NULL) (hopefully I get this right)... In match full, only the 1st and 4th fk values are valid. In match partial, the 1st, 2nd, and 4th fk values are valid. In match unspecified, all the fk values are valid. The other note is that generally speaking, all three are basically the same for the single column key. If you're only doing references on one column, the match type is mostly meaningless. > > PENDANT adds that for each row of the referenced table the values of > > the specified column(s) are the same as the values of the specified > > column(s) in some row of the referencing tables. > > I am not sure I know what you mean here.....Are you saying that the value for > the FK column must match the value for the PK column? I haven't really looked at PENDANT, the above was just a small rewrite of some descriptive text in the sql99 draft I have. There's a whole bunch of rules in the actual text of the referential constraint definition. The base stuff seems to be: (Rf is the referencing columns, T is the referenced table) 3) If PENDANT is specified, then: a) For a given row in the referencing table, let pendant reference designate an instance in which all Rf are non-null. b) Let number of pendant paths be the number of pendant references to the same referenced row in a referenced table from all referencing rows in all base tables. c) For every row in T, the number of pendant paths is equal to or greater than 1. So, I'd read it as every row in T must have at least one referencing row in some base table. There are some details about updates and that you can't mix PENDANT and MATCH PARTIAL or SET DEFAULT actions. > > The main issues in 7.0 are that older versions (might be fixed in > > 7.0.3) would fail very badly if you used alter table to rename tables that > > were referenced in a fk constraint and that you need to give update > > permission to the referenced table. For the former, 7.1 will (and 7.0.3 > > may) give an elog(ERROR) to you rather than crashing the backend and the > > latter should be fixed for 7.1 (although you still need to have write > > perms to the referencing table for referential actions to work properly) > > Are the steps to this outlined somewhere then? The permissions stuff is just a matter of using GRANT and REVOKE to set the permissions that a user has to a table.