Please reply to the list...
In short...
A natural key prevents duplicate real data which a serially generated made up key does not.
David J.
On Monday, November 17, 2014, Tim Dudgeon <
tdudgeon.ml@gmail.com> wrote:
On 17/11/2014 18:44, David G Johnston wrote:
Tim Dudgeon wrote
All relevant columns are indexed and using PostgreSQL 9.4.
Any clues how to re-write it to avoid the slow sub-query.
Try using an actual join instead of a subquery. You will have to provide
aliases and then setup the where clause appropriately.
I'm trying to go in that direction but in the query is entirely within one table, so I need to join the table to itself? I've been trying this but not getting it to work yet.
I am reading the query correctly in that the repeated reference to 643413 is
redundant?
In this example its sort of redundant, but in a real world case the query for structure_id and property_id are independent and may have nothing in common.
The lack of a defined natural primary key makes blind reasoning
difficult.
The id column is the primary key.
Tim
David J.
--
View this message in context: http://postgresql.nabble.com/slow-sub-query-problem-tp5827273p5827275.html
Sent from the PostgreSQL - sql mailing list archive at Nabble.com.