First forgive me for my English. It is a little bad. Second forgive my ignorance, i'm newiest in postgres
I'm having trouble when I try to up a backup database on another database. I need to dump the database just to get one table, but I only have the files that was in /var/lib/pgsql/data/base/
Here what I try:
I create a database named "test" with OID 227763 so I put the files of the old database to this new database with another OID. I fix the folder and files permissions, but when I log into "test" and run select * from pg_tables; the tables does not appears to me. And when I try to create the table on PhpPgAdmin, I got
ERROR: relation already exists
I'm trying to do this because I need to know which of this files is the table that i want. I will log into database and run SELECT oid,* from pg_class; to get the OID.
I found the old OID database in /var/lib/pgsql/data/global/pg_database
If anyone can help me, I thank you.
There are many ways to backup and restore an entire database or a single table. It sounds like you need to be using pgDump instead of working on individual files. A file level copy is likely to corrupt your database if not in backup mode and if not copying the entire thing + archive logs.
If you MUST copy it by files, make sure the database is shut down for maximum safety.
For me, if I had one table to backup, I'd use pg_dump
pg_dump -U {user-name} {source_db} -f {dumpfilename.sql}
you can use the -t flag to list a single table if you like.
I wanna ask something. i am not so good at this so thought i should ask here.
My previous server was crashed and they gave me my site's data back after some days of restoration. All i got was my site's data and everything. But they did not give me my sql database in ".sql" format. I just know a single way to import database from phpmyadmin. Now they gave me a folder with some "ibd", "frm", "MYD", "MYI" files. I dont know about how i can convert all these files into one single .sql file. Or how i can import my database from these. Please give me an easy solution because i am not used to the coding or command lines stuff.
These files are the "databases". Cit to thy mysql data directory, start mysql and your tables should be shown. The data Directory is different on different OS. So I can not say where it is.
Attention: the Version of the database which creates the files must be the same the Version do you use.
Here a link that can help you find the directory:
http://www.mkyong.com/mysql/where-does-mysql-stored-the-data-in-my-harddisk/
I am pretty new with postgresql and pgAdmin and I made a beginner error.
I changed the hard drive of my computer and unfortunately (and stupidly I really admit) I have not make a backup of my database in pgAdmin3 before. Is there anyway I can manage to transfer it back from my old hard drive to the new one?
I tried to copy the file "Data" of pgAdmin from the old hard drive to the new one but it did not succeed. Is there any hidden file that would retain information of my database still on the old hard drive?
If I re-install the old hard drive, would I be able to access the database back?
if anyone have any idea I would be really glad,
thanks
Do as "Richard Huxton" suggested, then
On Windows you need may need to set PG as a Service
Run the following on the command line (as adminstrator):
pg_ctl.exe register -N postgres -D "C:\Program Files\PostgreSQL\9.6\data"
Start the service
answer from:
Register and run PostgreSQL 9.0 as Windows Service
Three steps are required:
Copy everything in the data folder (base, global, ... pg_xlog, ...)
Make sure the permissions are right
Make sure you have the same version of the PostgreSQL binaries installed.
Then just point the configuration at it (data_directory) and start it up. If there are any problems, check the logs for details - it'll probably be permissions.
Sometimes it's convenient to do all this in a virtual machine if you have that sort of stuff set up already.
My EC2 database server failed, preventing SSH or other access (not sure why ... grrr AWS ... that's another story).
I was able to make a snapshot of the EBS root volume. I can not boot a new instance from this volume (I'm guessing the boot partition is corrupt). However, I can attach and mount the volume on a new instance.
Now I need to get the PostgreSQL 8.4 on the new machine (Ubuntu 10.04) to load the data from the mounted volume. Is this possible? I've tried:
pg_ctl start -D /<mount_dir>/etc/postgresql/8.4/main/
But no joy ... PostgreSQL just starts with empty tables.
Is /etc/postgresql/8.4/main/ the correct location for PostgreSQL data files?
Is there a way to recover the data from the mounted volume in a way that PostgreSQL can read again?
(You should really specify your distro and version, etc, with this sort of system admin question.)
Running Pg via pg_ctl as shown above should work, assuming the original database was from Pg 8.4 and so are the binaries you're trying to use to start it. Perhaps you forgot to stop the instance of PostgreSQL automatically started by the distro? Or connected on the wrong port, so you got the distro's default instance instead of your DB on another port (or different unix socket path, for unix sockets)?
Personally I wouldn't do what you're doing anyway. First, before I did anything else, I'd make a full backup of the entire data directory because you clearly don't have good backups, otherwise you wouldn't be worrying about this. Take them now, because if you break something while restoring you're going to hate yourself. As demonstrated by this fault, trusting Amazon's storage (snapshot or otherwise) probably isn't good enough.
Once you've done that: The easiest way to restore your DB will be to, on a new instance you know you don't have any important data on that has the same major version (eg "8.4" or "9.0") of postgresql as your original instance did installed:
/etc/init.d/postgresql-8.4 stop
datadir=/var/lib/postgresql/8.4/main
rm -rf "$datadir"
cp -aR /<mount_dir>/etc/postgresql/8.4/main/ "$datadir"
chown -R postgres:postgres "$datadir"
/etc/init.d/postgresql-8.4 start
In other words: take a copy, fix the permissions, start the DB.
You might need to edit /etc/postgresql/8.4/main/postgresql.conf and/or /etc/postgresql/8.4/main/pg_hba.conf because any edits you made to the originals aren't there anymore; they're on your corrupted root FS. The postgresql.conf and pg_hba.conf in the datadir are just symlinks to the ones in etc under Debian - something I understand the rationale behind, but don't love.
Once you get it running, do an immediate pg_dumpall and/or just a pg_dump of your important DB, then copy it somewhere safe.
I have the following problem and I need to know if thereĀ“s a way to fix it.
I have a client who was cheap enough to decline buying a backup plan for his postgreSQL databases on the main system that runs his company and as I thought it would happen some day, some OS files crashed during a blackout and the OS needs to be reinstalled.
This client didn't have any backups of the databases but I managed to save the PostgreSQL main directory. I read that the databases are stored somehow inside the data directory of the postgres main folder.
My question is: Is there any way to recover the databases from the data folder only? I am working in a windows environment (XP service pack 2) with PostgreSQL 8.2 and I need to reinstall PostgreSQL in a new server. I would need to recreate the databases in the new environment and somehow attach the old files to the new database instances. I know that's possible in SQL Server because of the way that engine stores the databases but I have no clue in postgres.
Any ideas? They would be much appreciated.
If you have the whole data folder, you have everything you need (as long as architecture is the same). Just try restoring it on another machine before wiping this one out, in case you didn't copy something.
Just save the data directory to disk. When launching Postgres, set the parameter telling it where the data directory is (see: wiki.postgresql.org). Or remove original data directory of the fresh installation and place the copy in its place.
This is possible, you just need to copy the "data" folder (inside the Postgres installation folder) from the old computer to the new one, but there are a few things to keep in mind.
First, before you copy the files, you must stop the Postgres server service. So, Control Panel->Administrative tools->Services, find Postgres service and stop it. When you're done copying the files and setting permissions, start it again.
Second, you need to set the permissions for the data files. Because postgres server actually runs on another user account, it will not be able to access the files if you just copy them into the data folder, because it will not have permissions to do so. So you need to change the ownership of the files to the "postgres" user. I had to use subinacl for this, install it first, and then use it from command prompt like this (first navigate to folder where you installed it):
subinacl /subdirectories "C:\Program Files\PostgreSQL\8.2\data\*" /setowner=postgres
(Changing ownership should also be possible to do from the explorer: first you must disable "Use simple file sharing" in Folder options, then a "Security" tab will appear in the folder Properties dialog, and there are options there to set permissions and change ownership, but I wasn't able to do it that way.)
Now, if the server service can't start after you start it manually again, you can usually see the reason in the Event viewer (Administrative tools->Event viewer). Postgres will throw an error event, and inspecting it will give you a clue about what the problem is (sometimes it will complain about a postmaster.pid file, just remove it, etc.).
The question is very old, but I want to share an effective method that I found.
If you have not got a backup with "pg_dump" and your old data is folder, try the following steps.
In the Postgres database, add records to the "pg_database" table. With a manager program or "insert into".
Make the necessary check and change the following insert query and run it.
The query will return an OID after it has worked. Create a folder with the name of this number. Once you have copied your old data into this folder, the use is now ready.
/*
------------------------------------------
*** Recover From Folder ***
------------------------------------------
Check this table on your own system.
Change the differences below.
*/
INSERT INTO
pg_catalog.pg_database(
datname, datdba, encoding, datcollate, datctype, datistemplate, datallowconn,
datconnlimit, datlastsysoid, datfrozenxid, datminmxid, dattablespace, datacl)
VALUES(
-- Write Your collation
'NewDBname', 10, 6, 'Turkish_Turkey.1254', 'Turkish_Turkey.1254',
False, True, -1, 12400, '536', '1', 1663, Null);
/*
Create a folder in the Data directory under the name below New OID.
All old backup files in the directory "data\base\Old OID" are the directory with the new OID number
Copy. The database is now ready for use.
*/
select oid from pg_database a where a.datname = 'NewDBname';
As shown by move database to another hard drive. All we need to do is to modify the registry table and file permissions. By modifying registry table(shown in image 1), postgresql server know the new location of data.
modify registry
If you have issues with permissions or with stuff like icacls during installation to old data folder then try my solution from sister website.
https://superuser.com/a/1611934/1254226
I do so but the most tricky part was to change the owner permission:
go to services from administative tools
find postgres service and double click on it
at log on tab change to local system
then restart