Hi Thomas, thanks for your answer. We decided not to go further with this error, because soon we will have another product that replaces this one. Because I want to learn more about this topic, I did the following:
Before I write your code, I tried: select oid,ctid,relname from pg_class where ctid='(4707,0)'; but it resulted in: oid | ctid | relname -----+------+--------- (0 rows) Isn't there suppose to be a ctid of '(4707,0)'? Or did I misunderstand what you have written? Regards, Deniz On Mon, Aug 1, 2011 at 1:21 PM, Tomas Vondra <t...@fuzzy.cz> wrote: > On 1 Srpen 2011, 8:27, Deniz Atak wrote: > > Deepak, Tom thanks for answering. > > > > Tom, we have psql 8.1.18. So you are right, this weird message is because > > of > > the old version. I will check with my colleague about the possible > > reasons. > > What can I do if there is a messed up table? > > First of all, you should find out what caused the mess. This could be > really difficult as it might be a rare hw or sw glitch. Anyway consider > upgrading to 8.1.23 if possible. > > If you have a fresh backup (i.e. one with all the data in the table), just > restore it and use it. You may even use just this particular table (just > move it using COPY). > > If you need to recover the data, you'll have to play a bit with it as you > need to 'skip' all the corrupted blocks. The query reports block 4707 is > corrupted - how many blocks does the relation have? > > You can skip the blocks using 'ctid' column, which is basically "(block > id, item id)" so to skip block 4707 you can do this > > SELECT * FROM table WHERE (ctid < '(4707,0)'::ctid OR ctid >= > '(4708,0)'::ctid) > > and if fails with another "could not read block" error, put there another > such condition. > > Tomas > > > >
