Thread: Database recovery

Database recovery

From
tony
Date:
Hi

In the doc I have "this section needs to be written"

I have a database system to recover any pointers greatly appreciated. My tape backup is two weeks old... I know that is
badbut I have to live with it. 

Cheers

Tony Grant

--
tony@animaproductions.com

JWebMail WebMail/Java v0.7.6 WWW to Mail Gateway

Re: Database recovery

From
Doug McNaught
Date:
tony <tony@animaproductions.com> writes:

> Hi
>
> In the doc I have "this section needs to be written"
>
> I have a database system to recover any pointers greatly
> appreciated. My tape backup is two weeks old... I know that is bad
> but I have to live with it.

Is it a backup of a dump file produced with pg_dump, or a backup of
the raw database files?

What have you tried so far?

-Doug
--
Let us cross over the river, and rest under the shade of the trees.
   --T. J. Jackson, 1863

Question about like

From
"Cornelia Boenigk"
Date:
Merry Christmas and hello everybody

I have a test table with a field called 'name' which have three
entries:
Johanna
Karl
Uwe

If I query this table with
- select name from test where name like 'Uwe';
- select name from test where name like 'U_e';
- select name from test where name like '%e';
or
- select name from test where name like '---';

in all cases pg responds with 0 rows found.

I was expecting another result;-(
Does anybody have a hint or an explanation for this behaviour?
My system is RedHat 7.1 with PostgreSQL 7.1.3

Many thanks
Conni



Re: Question about like

From
Joe Conway
Date:
Cornelia Boenigk wrote:

> Merry Christmas and hello everybody
>


And to you!

> I have a test table with a field called 'name' which have three
> entries:
> Johanna
> Karl
> Uwe
>
> If I query this table with
> - select name from test where name like 'Uwe';
> - select name from test where name like 'U_e';
> - select name from test where name like '%e';
> or
> - select name from test where name like '---';
>
> in all cases pg responds with 0 rows found.
>
> I was expecting another result;-(
> Does anybody have a hint or an explanation for this behaviour?
> My system is RedHat 7.1 with PostgreSQL 7.1.3
>

You haven't shown us how your "test" table is defined, but if "name" is
a CHAR() field, you need to allow for the spaces padded to the end of
'Ewe'. With TEXT or VARCHAR you don't need to worry about that. See the
examples below:


test=# create table test1(name text);
CREATE
test=# create table test2(name char(25));
CREATE
test=# create table test3(name varchar(25));
CREATE
test=# insert into test1 values('Uwe');
INSERT 1492521 1
test=# insert into test2 values('Uwe');
INSERT 1492522 1
test=# insert into test3 values('Uwe');
INSERT 1492523 1
test=# select name from test1 where name like 'Uwe';
  name
------
  Uwe
(1 row)

test=# select name from test1 where name like 'U_e';
  name
------
  Uwe
(1 row)

test=# select name from test1 where name like '%e';
  name
------
  Uwe
(1 row)

test=# select name from test2 where name like 'Uwe';
  name
------
(0 rows)

test=# select name from test2 where name like 'Uwe%';
            name
---------------------------
  Uwe
(1 row)

test=# select name from test2 where name like 'U_e';
  name
------
(0 rows)

test=# select name from test2 where name like 'U_e%';
            name
---------------------------
  Uwe
(1 row)

test=# select name from test2 where name like '%e';
  name
------
(0 rows)

test=# select name from test2 where name like '%e%';
            name
---------------------------
  Uwe
(1 row)

test=# select name from test3 where name like 'Uwe';
  name
------
  Uwe
(1 row)

test=# select name from test3 where name like 'U_e';
  name
------
  Uwe
(1 row)

test=# select name from test3 where name like '%e';
  name
------
  Uwe
(1 row)

test=# select version();
                            version
-------------------------------------------------------------
  PostgreSQL 7.2b3 on i686-pc-linux-gnu, compiled by GCC 2.96
(1 row)


Hope this helps,

Joe


Re: Database recovery

From
tony
Date:
You wrote:
> tony <tony@animaproductions.com> writes:
> > Hi
> >
> > In the doc I have "this section needs to be written"
> >
> > I have a database system to recover any pointers greatly
> > appreciated. My tape backup is two weeks old... I know that is bad
> > but I have to live with it.
> Is it a backup of a dump file produced with pg_dump, or a backup of
> the raw database files?

Raw database

> What have you tried so far?

Nothing yet too scared to break it more. I'll check the developpement docs now.

Cheers

Tony
--
tony@animaproductions.com

JWebMail WebMail/Java v0.7.6 WWW to Mail Gatewayy

Re: Database recovery

From
tony
Date:
You wrote:
> > In the doc I have "this section needs to be written"
> Check the new development docs. There is some content now.
> > I have a database system to recover any pointers greatly appreciated. My tape
> >backup is two weeks old... I know that i s bad but I have to live with it.
> You will need to give some hints on what the symptoms are.

Hardware failure. postmaster refuses to start. I don't know if anybody was writing to the database at the time.

cheers

tony


--
tony@animaproductions.com

JWebMail WebMail/Java v0.7.6 WWW to Mail Gatewaya

Re: Question about like

From
"Cornelia Boenigk"
Date:
Hi Joe

> but if "name" is
> a CHAR() field, you need to allow for the spaces padded to the
end

This was exactly the problem.
Thank you

Conni