SET READ ONLY forgets previous changes

[monetdb-team]

Date: 2014-02-27 12:11:44 +0100
From: @swingbit
To: SQL devs <>
Version: 11.15.19 (Feb2013-SP6)
CC: @njnes

Last updated: 2014-05-22 09:52:26 +0200

Comment 19642

Date: 2014-02-27 12:11:44 +0100
From: @swingbit

User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/32.0.1700.102 Safari/537.36
Build Identifier:

create table t(a int);
insert into t values (1),(3),(2),(3),(3),(3);

select * from t;

-- remove the 3s
delete from t where a = 3;
select * from t;

-- Oops, the 3s are back when the table is set read-only
alter table t set read only;
select * from t;

-- Oops, the 3s are gone again when the table is read/write again
alter table t set read write;
select * from t;

Reproducible: Always

$ mserver5 --version
MonetDB 5 server v11.15.20 (64-bit, 64-bit oids)
This is an unreleased version
Copyright (c) 1993-July 2008 CWI
Copyright (c) August 2008-2013 MonetDB B.V., all rights reserved
Visit http://www.monetdb.org/ for further information
Found 15.6GiB available memory, 8 available cpu cores
Libraries:
libpcre: 8.33 2013-05-28 (compiled with 8.32)
openssl: OpenSSL 1.0.1e 11 Feb 2013 (compiled with OpenSSL 1.0.1e-fips 11 Feb 2013)
libxml2: 2.9.1 (compiled with 2.9.1)
Compiled by: roberto@photon.spinque.com (x86_64-unknown-linux-gnu)
Compilation: gcc -g -Werror -Wall -Wextra -W -Werror-implicit-function-declaration -Wpointer-arith -Wdeclaration-after-statement -Wundef -Wformat=2 -Wno-format-nonliteral -Winit-self -Winvalid-pch -Wmissing-declarations -Wmissing-format-attribute -Wmissing-prototypes -Wold-style-definition -Wpacked -Wunknown-pragmas -Wvariadic-macros -fstack-protector-all -Wstack-protector -Wpacked-bitfield-compat -Wsync-nand -Wjump-misses-init -Wmissing-include-dirs -Wlogical-op -Wunreachable-code
Linking : /usr/bin/ld -m elf_x86_64

Comment 19652

Date: 2014-02-28 11:22:10 +0100
From: @swingbit

For completeness: this is not just related to deletions, but to all updates

Comment 19707

Date: 2014-03-26 11:35:55 +0100
From: @njnes

deletes are now properly kept even with read only. When there are updates the set read only will now fail, unless the updates have be flushed (ie are consumed by the base/central columns etc).

Comment 19708

Date: 2014-03-26 11:48:58 +0100
From: MonetDB Mercurial Repository <>

Changeset 5e7f1c747884 made by Niels Nes niels@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=5e7f1c747884

Changeset description:

fixed bug #3446, ie readonly needs to use the 'tid' column and only
set to read only when there are no (unflushed) updates.