Responses inline.

On 26/01/2015 12:13, Christian Grün wrote:

Hi Marco,

I'm sorry to hear your database got corrupted. Once a database has inconsistent structures, it's difficult to restore its original state. Some questions that might help:

Yeah. I was aware of this. I hoped that the problem could be at least identifiable because of the clear inspect outcome.

1. Can you do a full optimization via db:optimize('db', true())?

Before calling the command, I would recommend you to create a backup of your database.

No. We try to run it through command "optimize all" which should be the same but this is where we get the attribute serializetion error.

2. Can you successfully serialize or export your database?

No. We copied the DB to another machine and tried to import into another basex. The import actually succeeds but a simple query on the root tag of all the documents shows up only 10 percent of the actual data.

3. Did you do any backups during the last months that may help us to

find the first corrupt database version?

Yes. The problem showed up in Friday's logs files and we have a nightly backup (Thursday to Friday) which looks healty.

4. Which version(s) of BaseX did you use?

It's "BaseX 8.0 beta 2cc72a0". M.

...

Hi all, we have an installation that has been running in production for nearly two months now. It's very insertion intensive and from time to time we need to run a db:optimize to keep it on track because the time it takes to serve a request turns from about 2 seconds to 100k seconds. But after the optimize it again runs with the expected performance. Today we noticed again a strange difficulty in serving requests so we tried the usual approach but we got this exception during the optimize:

[SENR0001] Attributes cannot be serialized:attribute determinerCode {"INSTA....

Upon running an inspect command, we got a long list of EOF exceptions followed by the resume stating about 85K wrong parent/descendants relationships.

Is there any idea on what could have gone wrongly and if possible any way to recover from this? Thank you very much. Regards, Marco.

java.io.EOFException at java.io.RandomAccessFile.readFully(RandomAccessFile.java:446) at java.io.RandomAccessFile.readFully(RandomAccessFile.java:424) at org.basex.io.random.TableDiskAccess.readBlock(TableDiskAccess.java:525) at org.basex.io.random.TableDiskAccess.readPage(TableDiskAccess.java:489) at org.basex.io.random.TableDiskAccess.cursor(TableDiskAccess.java:468) at org.basex.io.random.TableDiskAccess.read1(TableDiskAccess.java:148) at org.basex.data.Data.kind(Data.java:290) at org.basex.core.cmd.Inspect.inspect(Inspect.java:50) at org.basex.core.cmd.Inspect.run(Inspect.java:27) at org.basex.core.Command.run(Command.java:360) at org.basex.core.Command.execute(Command.java:94) at org.basex.api.client.LocalSession.execute(LocalSession.java:122) at org.basex.api.client.Session.execute(Session.java:36) at org.basex.core.CLI.execute(CLI.java:106) at org.basex.core.CLI.execute(CLI.java:90) at org.basex.BaseX.console(BaseX.java:197) at org.basex.BaseX.<init>(BaseX.java:171) at org.basex.BaseX.main(BaseX.java:42) Checking main table (43626334 nodes):

• 0 invalid node kinds
• 0 invalid parent references
• 84663 wrong parent/descendant relationships (pre: 6299342,..)

Warning: Database is inconsistent. 'db' inspected in 21789.24 ms.