Inserted_at seems buggy in production mode?


#1

Hi,

I’ve got a table with an inserted_at column. When I insert a record it
automatically injects the current date/time, all is well.
Then when I insert a second record, it uses the exact same timestamp
that is used in the first record.

This behavior only seems to occur in production mode. When I restart the
server, the problem goes away but then immidetatly occurs again on the
second insert. I’m using postgresql 8.1 and I have my default value for
the inserted_at column set to now().

Any ideas??

Jeroen

— below is some log output ----

Processing MatchController#comment (for 192.87.30.169 at 2006-03-16
12:23:41) [POST]
Parameters: {“mc”=>{“body”=>“testtest”}, “commit”=>“Een moment …”,
“action”=>“comment”, “id”=>“159”, “controller”=>“match”}
Match Load (0.001001) SELECT * FROM matches WHERE (matches.id =
‘159’) LIMIT 1
SQL (0.000319) BEGIN
PK and serial sequence (0.017476) SELECT attr.attname,
name.nspname, seq.relname
FROM pg_class seq,
pg_attribute attr,
pg_depend dep,
pg_namespace name,
pg_constraint cons
WHERE seq.oid = dep.objid
AND seq.relnamespace = name.oid
AND seq.relkind = ‘S’
AND attr.attrelid = dep.refobjid
AND attr.attnum = dep.refobjsubid
AND attr.attrelid = cons.conrelid
AND attr.attnum = cons.conkey[1]
AND cons.contype = ‘p’
AND dep.refobjid = ‘match_comments’::regclass

MatchComment Create (0.002280) INSERT INTO match_comments (“body”,
“match_id”, “player_id”, “inserted_at”) VALUES(‘testtest’, 159, 14,
‘2006-03-16 12:22:55’)
SQL (0.000684) SELECT currval(‘public.match_comments_id_seq’)
SQL (0.034973) COMMIT
Redirected to http://tcuithof.laddertennis.nl/match/show/159

Processing MatchController#comment (for 192.87.30.169 at 2006-03-16
12:24:57) [POST]
Parameters: {“mc”=>{“body”=>“test”}, “commit”=>“Een moment …”,
“action”=>“comment”, “id”=>“159”, “controller”=>“match”}
Match Load (0.001003) SELECT * FROM matches WHERE (matches.id =
‘159’) LIMIT 1
SQL (0.000327) BEGIN
MatchComment Create (0.000929) INSERT INTO match_comments (“body”,
“match_id”, “player_id”, “inserted_at”) VALUES(‘test’, 159, 14,
‘2006-03-16 12:22:55’)
SQL (0.000448) SELECT currval(‘public.match_comments_id_seq’)
SQL (0.036623) COMMIT

Processing MatchController#comment (for 192.87.30.169 at 2006-03-16
12:26:00) [POST]
Parameters: {“mc”=>{“body”=>“dsasda”}, “commit”=>“Een moment …”,
“action”=>“comment”, “id”=>“159”, “controller”=>“match”}
Match Load (0.001013) SELECT * FROM matches WHERE (matches.id =
‘159’) LIMIT 1
SQL (0.000307) BEGIN
MatchComment Create (0.000991) INSERT INTO match_comments (“body”,
“match_id”, “player_id”, “inserted_at”) VALUES(‘dsasda’, 159, 14,
‘2006-03-16 12:22:55’)
SQL (0.000462) SELECT currval(‘public.match_comments_id_seq’)
SQL (0.034870) COMMIT


#2

Jeroen H. wrote:

Hi,

I’ve got a table with an inserted_at column. When I insert a record it
automatically injects the current date/time, all is well.
Then when I insert a second record, it uses the exact same timestamp
that is used in the first record.

Okay I should have searched for this before I posted
http://dev.rubyonrails.org/ticket/2257

More logic to move out of the database. I may as well start using
SQLite! :wink:

Jeroen


#3

I think your problem is related to this ticket:
http://dev.rubyonrails.org/ticket/2257
In production mode default value is cached right after the first query
for table columns metadata, so it will be the same on subsequent
requests.

You could rename ‘inserted_at’ to ‘created_at’ and use Rails magic of
ActiveRecord::Timestamp mixin (active_record/timestamp.rb)


#4

Lugovoi N. wrote:

I think your problem is related to this ticket:
http://dev.rubyonrails.org/ticket/2257
In production mode default value is cached right after the first query
for table columns metadata, so it will be the same on subsequent
requests.

You could rename ‘inserted_at’ to ‘created_at’ and use Rails magic of
ActiveRecord::Timestamp mixin (active_record/timestamp.rb)

Thanks!

Aha I thought it should be called inserted_at, but created_at is the
special column name. My bad!

So if I do that, what should I use as my column definition? NOT NULL?
And no default value?

Jeroen