Re: unexpected error " tables can have at most 1600 columns"

["Day, David" <dday@xxxxxxxxxx>]

Pavel,

 

Thanks so much. This seems to help explain the  problem.

 

I can say that the patch file had a later statement with  an error related to search_path setup.

Given that the logic that applies patches repeat attempts for an extended period of time,

I speculate that the rollback of the patch leaves these invisible columns remaining?

Otherwise I fail to see  from where these columns originate.

 

When I drop the database and recreate it with the schema reference issues resolved.

( ie. Issues related to search_path  setup ). The database builds without issue.

 

These patches were not an issue for ongoing developers because at some point

In the installation the default search_path gets setup so that this err in the

patch writing is masked.

 

 

Thanks so much.

 

 

 

Regards

 

 

Dave Day

 

 

 

select attname from pg_attribute where attrelid='log.conference_history'::regclass and attnum > 0;

             attname

---------------------------------

........pg.dropped.11........

........pg.dropped.13........

........pg.dropped.14........

........pg.dropped.15........

........pg.dropped.41........

........pg.dropped.56........

........pg.dropped.42........

........pg.dropped.43..

 

select count(*) from pg_attribute where attrelid='log.conference_history'::regclass and attnum > 0 and attisdropped;

count

-------

  1598

 

From: Pavel Stehule [mailto:pavel.stehule@xxxxxxxxx]
Sent: Monday, April 13, 2015 12:06 PM
To: Day, David
Cc: pgsql-general@xxxxxxxxxxxxxx
Subject: Re: [GENERAL] unexpected error " tables can have at most 1600 columns"

 

 

 

2015-04-13 17:57 GMT+02:00 Day, David <dday@xxxxxxxxxx>:

Situation

 

I have a co-developer installing a new Virtual Machine and encountering a postgres error during the installation.

One of our  SQL patch files is failing unexpectedly. 

 

The patch is attempting to add columns to a table,  The table involved  currently has only 2 columns,

Interactively I can generate the same error in his current state.

 

psql -h ohio -U redcom ace_db

psql (9.3.6)

Type "help" for help.

 

ace_db=# select * from log.conference_history;

conf_id | max_size

---------+----------

(0 rows)

 

ace_db=# ALTER TABLE log.conference_history ADD talker_limit integer DEFAULT 0;

ERROR:  tables can have at most 1600 columns

ace_db=#

ace_db=#

 

There can be removed (invisible columns)

select attname from pg_attribute where attrelid = 'test'::regclass and attnum > 0;

postgres=# select attname from pg_attribute where attrelid = 'test'::regclass and attnum > 0;
┌─────────┐
│ attname │
╞═════════╡
│ a       │
│ c       │
│ d       │
└─────────┘
(3 rows)



alter table test drop column a, drop column c;


postgres=# select attname from pg_attribute where attrelid = 'test'::regclass and attnum > 0;
┌──────────────────────────────┐
│           attname            │
╞══════════════════════════════╡
│ ........pg.dropped.1........ │
│ ........pg.dropped.2........ │
│ d                            │
└──────────────────────────────┘
(3 rows)

postgres=# select count(*) from pg_attribute where attrelid = 'test'::regclass and attnum > 0 and attisdropped;
┌───────┐
│ count │
╞═══════╡
│     2 │
└───────┘
(1 row)

So maybe it can be a reason of this issue?

Pavel

 

 

 

 

Puzzled ?

 

 

Any thoughts ?

 

 

Regards

 

 

Dave Day