Re:Online bug? Tech Support clam it isn't

Tell me something, if you set your lock mode to row in the create table statement, do you still get this behaviour? At 05:42 PM 2/8/98 EDT, Peter Tashkoff wrote: > >It is not a bug. >You need the index to navigate the table. If you have no index each row must be tested in a sequential read to see whether it meets the criteria for update. The first thing that Online does is to place a lock on the row, for the committed read. Since you are operating within a singleton transaction this lock will not be released until your transaction is committed. Not only is this 'Just the way it works', it is IMO, sound design. > >It is a good idea to always navigate the table using indexes as sequential reads for updates can also cause deadlocks between applications which are trying to access totally unrelated rows. > >rgds > >Peter Tashkoff <tashkop@iname.com> >Zespri International Limited. Standard Disclaimers apply >All rights reserved, no party may use this document to vilify another > >Zespri New Zealand Kiwifruit, The Worlds Finest > >>>> Dave Cook <dave.cook@excelsis.co.uk> 7/02/98 06:10:29 >>> > >Any opinions on whether the following is a bug? Tech Support tell me it >isn't as it's "just the way it works". > >Online 7.22 is the culprit > >When performing an update, a lock is placed on all rows scanned in the >table, unless the update statement uses a unique index > >e.g. (very simple example) > >create table dave (col1 integer, col2 integer); >create index i_dave on dave(col1); >insert into dave values ( 1, 10 ); >insert into dave values ( 2, 20 ); >insert into dave values ( 3, 30 ); >insert into dave values ( 4, 40 ); >insert into dave values ( 5, 50 );>begin work; >update dave set col2 = 100 where col1 = 1;> >If I then (before committing) switch to another screen and update a >completely different row in the table by doing the following: > >begin work; >update dave >set col2 = 1000 where col1 = 5 > >I get the error: >-244 Could not do physical order read to get next row >-107 Record is locked > >If I create the index "i_dave" as unique I do not get the error. > >Thanks, >-- >Dave Cook > Best regards, Nigel +-------------------------------------------------------------+ |Name : Edmund Nigel Gall Tel: (868) 636 3153 | |Title : Information Systems Specialist Fax: (868) 679 3770 | |Company: Process Plant Services Limited | |Address: Atlantic Avenue, Point Lisas Industrial Estate | | Point Lisas, Couva, Trinidad & Tobago, W.I. | +----- mailto:nigelg@ppsl.com ------ http://www.ppsl.com -----+