I will try to answer this more carefully tomorrow morning.
For now just let me say that I have heard there is a bug about keys not being actually
removed; I will try to think about this when I have time tomorrow morning.
I am not sure what the problem is with the timestamps; but I have done things very similar
to what you are trying, so I assume we will be able to get it to work.
On Sat, 2006-04-08 at 11:26 +0300, Aycan iRiCAN wrote:
Hi,
Firstly, I want to thank you again for this great project.
Let me ask some questions. What is the difference between using
get-instances-by-class and using cursors?
When I use get-instances-by-class I get every instance (including
deleted keys) of the class. But when I use cursors, I only get
existing keys.
HEDEE> (get-instances-by-class 'user)
(#<USER "test" 3353473039> #<USER "aycan" 3353182543>)
HEDEE> (remove-kv 5 *hedee-users*)
T
HEDEE> (get-instances-by-class 'user)
(#<USER "test" 3353473039> #<USER "aycan" 3353182543>)
HEDEE> (with-transaction ()
(with-btree-cursor (c *hedee-users*)
(loop
for (m k v) = (multiple-value-list
(cursor-first c))
then (multiple-value-list (cursor-next c))
while m
collect v into users
finally (return (nreverse users)))))
(#<USER "aycan" 3353182543>)
Is it possible to completely remove a key from a btree?
Say I have a class named user (used above):
(defclass user ()
((id :accessor id :initarg :id :type integer
:initform (next-id)
:index t)
(name :accessor name :initarg :name
:initform nil :index t)
(epitaph :accessor epitaph :initarg :epitaph
:initform nil)
(image-type :accessor image-type :initarg :image-type :type string
:initform nil)
(timestamp :accessor timestamp :initarg :timestamp :type integer :index t
:initform (get-universal-time)))
(:metaclass persistent-metaclass))
and I created secondary indices via:
(defun add-indices ()
(with-transaction ()
(add-index *hedee-users*
:index-name 'id :key-form '(lambda (s key value)
(declare (ignore s key))
(values t (id value))))
(add-index *hedee-users*
:index-name 'name :key-form '(lambda (s key value)
(declare (ignore s key))
(values t (name value))))
(add-index *hedee-users*
:index-name 'timestamp :key-form '(lambda (s key value)
(declare (ignore s key))
(values t (timestamp value))))))
I tried to get users with a timestamp around some delta (320000 in
below) via:
(get-instances-by-range 'user
(get-index *hedee-users* 'timestamp)
(get-universal-time)
(- (get-universal-time) 320000))
But I'm getting:
The value 3353473355 is not of type FIXNUM.
How can I query by range using a timestamp?
Best Regards,
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