Re: strangest thing happened

On 07/07/2010 12:59 PM, John wrote:
> I am the only developer, DBA etc.. for a small project. Today (yesterday was
> everything was perfect) many of the sequence numbers fell behind what is the
> actual PK value. For example the invoice PK sequence current value = 1056
> but the table PK was 1071. Nobody (other than myself) knows how to
> edit/access the postgres server. So
>
> 1. Does anyone know how this could have happened?????? Other than human
> interaction.

I've never heard of this happening. Are you certain nothing bypassed the
sequence and directly inserted a PK value?

> 2. Does anyone have a script to reset the sequences to match the tables?

Not heavily tested, but something like this might do the trick:

8<----------------------
CREATE OR REPLACE FUNCTION adjust_seqs(namespace text)
RETURNS text AS $$
DECLARE
rec record;
startval bigint;
sql text;
seqname text;
BEGIN
FOR rec in EXECUTE 'select table_name, column_name, column_default
from information_schema.columns
where table_schema = ''' || namespace || '''
and column_default like ''nextval%''' LOOP

seqname := pg_get_serial_sequence(rec.table_name, rec.column_name);
sql := 'select max(' || rec.column_name || ') + 1 from ' ||
rec.table_name;
EXECUTE sql INTO startval;
IF startval IS NOT NULL THEN
sql := 'ALTER SEQUENCE ' || seqname || ' RESTART WITH ' ||
startval;
EXECUTE sql;
RAISE NOTICE '%', sql;
END IF;
END LOOP;
RETURN 'OK';
END;
$$ LANGUAGE plpgsql STRICT;

select adjust_seqs('public');
8<----------------------

HTH,

Joe

--
Joe Conway
credativ LLC: http://www.credativ.us
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