Thread

1. Comments on Database Broken

   PostgreSQL Bugs List <pgsql-bugs@postgresql.org> — 2001-05-21T18:23:30Z

   Patricia Holben (pholben@greatbridge.com) reports a bug with a severity of 3
   The lower the number the more severe it is.
   
   Short Description
   Comments on Database Broken
   
   Long Description
   When comments are added to a database (testdb in this example) (either at the point of creation or using the "comment on database ..." command) they may be stored either at the system level or within the individual database storage area.  Depending on how the user is connected, the "\l+" command may show the system comment on testdb (connected to template1 for example) OR the self-applied comment on testdb (connected to testdb) OR the local comment on testdb (connected to a different db which has made comments on what the other dbs are).  When a pg_dumpall command is executed, the dbs are dropped, and then the dump file is reloaded, only the self-applied comments exist anymore.  Mainly this is just confusing.  Maybe they should only exist in the system area  but be accessible to all.
   
   Sample Code
   
   
   No file was uploaded with this report
   
   
   

2. Re: Comments on Database Broken

   Tom Lane <tgl@sss.pgh.pa.us> — 2001-05-21T19:09:41Z

   pgsql-bugs@postgresql.org writes:
   > When comments are added to a database (testdb in this example) (either
   > at the point of creation or using the "comment on database ..."
   > command) they may be stored either at the system level or within the
   > individual database storage area.
   
   There is no such thing as comments "stored at the system level".
   Comments live in pg_description which is a per-database table.
   I think you are confusing the behavior of comments stored in template1
   (which will get copied to subsequently-created databases) with a
   true installation-wide table.
   
   We could theoretically answer this by making a pg_global_description
   table that is installation-wide like pg_database, but I'm not convinced
   that it's worth worrying about.  I'm not even convinced that the
   behavior is wrong: why shouldn't each DB be able to have its own comment
   on the other DBs?
   
   			regards, tom lane
   
   

3. Re: Comments on Database Broken

   Tom Lane <tgl@sss.pgh.pa.us> — 2001-05-21T19:30:48Z

   Patricia Holben <pholben@greatbridge.com> writes:
   > I only logged it today because I just
   > realized that they didn't all come back after the dump/restore.
   
   Hmm ... yeah, you're right, because pg_dump dumps comments along with
   the objects they refer to --- and a database is not an object within
   any other database.
   
   The same would probably happen to comments on users and groups (do we
   support those?).
   
   Not clear to me if this is fixable, or worth fixing, within the
   separate-dump-per-database framework of pg_dump.  Philip, any thoughts?
   
   			regards, tom lane
   
   

4. Re: Comments on Database Broken

   Bruce Momjian <pgman@candle.pha.pa.us> — 2001-05-22T11:38:49Z

   Good analysis.  Database comments are particularly tricky because
   pg_description exists in every database, but is unique.  To fix this, we
   would need a global pg_description table that would be used _just_ for
   database comments.
   
   > Patricia Holben (pholben@greatbridge.com) reports a bug with a
   > severity of 3 The lower the number the more severe it is.
   > 
   > Short Description Comments on Database Broken
   > 
   > Long Description When comments are added to a database (testdb
   > in this example) (either at the point of creation or using the
   > "comment on database ..." command) they may be stored either at
   > the system level or within the individual database storage area.
   > Depending on how the user is connected, the "\l+" command may
   > show the system comment on testdb (connected to template1 for
   > example) OR the self-applied comment on testdb (connected to
   > testdb) OR the local comment on testdb (connected to a different
   > db which has made comments on what the other dbs are).  When a
   > pg_dumpall command is executed, the dbs are dropped, and then
   > the dump file is reloaded, only the self-applied comments exist
   > anymore.  Mainly this is just confusing.  Maybe they should only
   > exist in the system area  but be accessible to all.
   > 
   > Sample Code
   > 
   > 
   > No file was uploaded with this report
   > 
   > 
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