Ubuntu is a desktop and server operating system based on Debian GNU/Linux. Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.

learn more… | top users | synonyms

27
votes
3answers
67k views

List the database privileges using psql

I'm in the middle of a database server migration and I can't figure (after googling and searching here) how can I list the database privileges (or all the privileges across the server) on PostgreSQL ...
20
votes
1answer
44k views

How to connect to an remote PostgreSQL database on Ubuntu using pgAdmin3?

I´m trying to setup an PostgreSQL database on an Ubuntu machine. I would like to be able to access it using pgAdmin3 from a remote machine. How do I setup this? I have installed the PostgreSQL ...
15
votes
3answers
35k views

How to make MySQL table name case insensitive in Ubuntu?

I am using Ubuntu 13.10 and MySQL 5.6 and I know database name and table name are case sensitive in Ubuntu (and some other *nix environments) by default. Now, I want to make MySQL work as case ...
13
votes
2answers
11k views

Preventing PostgreSQL from starting on boot in Ubuntu

I am using PostgreSQL 9.2 and it runs automatically when I start the system (Kubuntu). How can I avoid this? I need to start it manually, and I don't want it to start unattended because I need to ...
10
votes
3answers
8k views

Upstart script in ubuntu for mongodb

I am new to linux and mongodb. I've already installed mongodb on ubuntu but I want to run one more instance on different port. As I understood from other questions and forums , there must be upstart ...
9
votes
2answers
4k views

View Postgresql Memory Usage

I'm running Postgresql on a Ubuntu server and need to be able to monitor its memory usage. Currently I have scripts running in a one-minute cron job that monitor/log various statistics and need to ...
9
votes
2answers
8k views

How to Install/Configure Oracle Instant Client on Ubuntu

Installing the Oracle Instant Client on Ubuntu/Debian based systems is awkward since Oracle is RPM centric regarding its Linux support. What's the best way to easily install and configure the Instant ...
7
votes
2answers
4k views

How to run specific version (8.4, 9.1) of postgresql pg_* command (e.g., pg_dump)

I have Postgresql versions 8.4 and 9.1 installed. For any given Postgresql command, how do I specify a specific version of the command to run? (e.g., psql, pg_dump, pg_ctlcluster, pg_restore, ...) ...
6
votes
2answers
10k views

Redis takes up all the Memory and Crashes

A redis server v2.8.4 is running on a Ubuntu 14.04 VPS with 8 GB RAM and 16 GB swap space (on SSDs). However htop shows that redis alone is taking up 22.4 G of memory! redis-server eventually crashed ...
6
votes
2answers
9k views

mysql multi threading for a single query

I have big db of size 8GB and having 9 million contacts in this db. When we try to retrieve all contacts, it takes nearly 1 or 2 hour (in some cases result in timeout) to retreive all contacts for the ...
6
votes
1answer
2k views

Substantial difference between database size under MySQL and actual size on disk

When I check the size of my databases under MySQL I get this: MariaDB [(none)]> SELECT table_schema "Data Base Name", sum( data_length + index_length ) / 1024 / 1024 "Data Base Size in MB", sum(...
5
votes
5answers
10k views

MySQL said “InnoDB: Initializing buffer pool, size = 128.0M”, does it mean it is using 128MB RAM?

I am just using a very few InnoDB tables (e.g. less than 1MB), but during MySQL startup, it said InnoDB: Initializing buffer pool, size = 128.0M Does it mean even I am using in such a small size, ...
5
votes
4answers
4k views

could not save history to file “/var/lib/postgresql/.psql_history”: No such file or directory

I'm following this tutorial to set up my postgresql db. http://inventtheweb.blogspot.ca/2012/05/install-postgresql-for-django.html After I finish running the CREATE DATABASE command and run \q I ...
5
votes
2answers
10k views

Error: couldn't connect to server 127.0.0.1:27017 src/mongo/shell/mongo.js:91 when changing mongodb data directory

I already change the owner of the directory I want to use root@ip-10-138-30-205:/media/newdrive# ls -l ...
5
votes
2answers
2k views

Trying to get multiple mysql instances running on Ubuntu dev box

I'm trying to get multiple instances of mysql running on a dev box for some testing. This guy is running ubuntu so the setup's a little different than our production setups. I'd like to find the ...
5
votes
2answers
1k views

MySQL queries are 10 to 100 times slower after OS reboot

I have a MySQL server running on Ubuntu. If I restart the MySQL, everything is fine. If I however restart the OS, my queries take anywhere from 10 times to 100 times as long. The only "solution" to ...
5
votes
3answers
2k views

Install PostGIS v2 for PostgreSQL v9.2

I have installed the latest stable version of PostgreSQL v9.2 and I want to install the PostGIS v2 extension. I've been searching for it for 3 days now, however can't find it. I did however find ...
4
votes
2answers
3k views

PostgreSQL: SET-ing from psql arguments

Following this answer regarding limiting resources per query in PostgreSQL, I've been advised to set a timeout value for query execution: SET statement_timeout TO '1min'; This is great, but ...
4
votes
2answers
2k views

What's a free client for Oracle 8 on Linux / Ubuntu? [closed]

I need to connect to a legacy Oracle 8 database. Oracle SQL Developer would be my tool of choice, but the current version doesn't support Oracle 8 anymore. I tried Squirrel too, but the connection ...
4
votes
2answers
3k views

Recover PostgreSQL database from WAL errors on startup?

I'm trying to set up an OpenStreetMap server on an Ubuntu 12.04 machine using the Ubuntu packages listed at switch2osm.org. I initially installed and set up everything using a Northeast US-only map ...
4
votes
1answer
13k views

Connection to an oracle db from another computer

I have installed Oracle 11g to an ubuntu, I can connect to DB using sqlplus from the localhost, But I cannot connect from another computer, I have configured my tnsnames.ora as followed; ELIF = (...
4
votes
1answer
7k views

How to set a specific directory location for individual MySQL database?

Is it possible to set each database in MySQL to use a separate datadir? I'm running a userdir development (sandbox) server and would like to put the MySQL data files for the database(s) for that user ...
4
votes
1answer
3k views

Difference between mongod and mongodb upstart jobs

I just noticed that there are two possible ways to start mongodb: service mongodb start (uses /etc/mongod.conf) service mongod start (uses /etc/mongodb.conf) Can someone tell me what's the ...
4
votes
5answers
2k views

MySQL runs out of memory when importing innodb database

I have a small VPS with 512MB RAM and no swap (can't have any). I am importing a 1.5GB innodb database with mysql -u -p < database.sql Before the operation can finish it says : Lost connection ...
4
votes
3answers
1k views

PostgreSQL: Extending database storage when disk is full

I have a database that takes about 60GB in my disk storage. And it doesn't alow to insert into database anymore. I have read the documentation about tablespaces link But It's like create space for a ...
4
votes
1answer
6k views

Enable MySQL to use more than 1 core (multicore) [duplicate]

I am running a very intensive MySQL query and noticed that only 1 core is being used to 100% while the other cores are idle. The system is running Ubuntu 12.04 and MySQL 5.5.28 Is there a way to ...
4
votes
0answers
413 views

MySQL 5.7 + Ubuntu 14.04 eating up my RAM

I've recently installed MySQL 5.7.11 in my Ubuntu 14.04.3 system following these instructions: http://dev.mysql.com/doc/mysql-apt-repo-quick-guide/en/ Being totally empty and not being called by any ...
4
votes
1answer
11k views

Moving postgresql data directory

I moved postgresql's data directory by following the following steps: Stop postgres cp -a source_data_directory destination_data_directory export PGDATA=destination_data_directory Changing data ...
3
votes
1answer
6k views

Mysql error 28 no space left on the device

I keep running in to the same problem with mysql with error code 28 which means there is not enough space left on the device. Now the weird part is that there is enough space, here are some tips i ...
3
votes
2answers
9k views

How to dump PostgreSQL database whose owner has no password?

First, some background on my setup: The server has root access disabled. So, I log-in as (say) john who also belongs to the sudo group and is therefore able to run superuser commands. I created a ...
3
votes
1answer
5k views

mysql works, mysqldump doesn't

I have mysql 5.5 on my ubuntu 12.04 server. This command: mysql -u root -p works perfectly, but this gives me error: mysqldump -u root -p mydb_name > a.sql mysqldump: Got error: 2002: Can't ...
3
votes
4answers
14k views

How to Add Federated engine after installing Mysql

I have Mysql 5.5.18 and upon show engines: show engines; +--------------------+---------+------------------------------------------------------------+--------------+------+------------+ | Engine ...
3
votes
2answers
6k views

Postgresql - Recovery using recovery.conf

I am trying to recover a database using recovery.conf file for making point-in-time copy. On recovery.conf file, I added a recovery target time as below. recovery_target_time = '2011-06-16 04:10:00 ...
3
votes
2answers
4k views

Install MariaDB 10 on Ubuntu without prompt and no root password

Pretty much the same as this question but I don't want to have a root password (this is just a dev machine). Here's what I've got: export DEBIAN_FRONTEND=noninteractive sudo debconf-set-selections &...
3
votes
1answer
7k views

sqldeveloper ORA-12505. TNS: listener does not currently know of SID given in connect descriptor

There are similar questions asked and answered in this network related to the error message given in the question, however this problem is a little different from each. I have installed oracle 12c in ...
3
votes
1answer
7k views

Very poor insert performance MySQL / Percona Server

I'm running a Percona-Server instance off an Ubuntu server install. I'm using an application that needs to access this database, and its having VERY poor performance. Once the database has been ...
3
votes
2answers
6k views

Mysql consumes a lot of memory

Here is my situation. I have an ubuntu server monitored by nagios. recently nagios sends alarms regarding the memory consumption on the server. I logged into the server and executed the top command ...
3
votes
2answers
4k views

Install MariaDB without password prompt in Ubuntu

I need to install MariaDB server in Ubuntu without password prompt. For this purpose, I execute the following commands, but it doesn't gave me any progress. It again shows password prompt. I used the ...
3
votes
1answer
666 views

oracle 11g seems to die every 2 days, how can i debug what's happening?

I installed oracle 11g on ubuntu 11.10, but it seems that every couple of days I'll get to work and the database isn't running but the listener is. To fix it, all I have to do is login and start it ...
3
votes
1answer
766 views

current_timestamp default column value working in Windows but not in Linux

This MySql query runs fine in Windows: CREATE TABLE `posts`.`table` ( `idTable` INT NOT NULL AUTO_INCREMENT, `Column1` DATETIME NULL DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (`idTable`)); In ...
3
votes
1answer
272 views

Very large btree index with few rows (openstreetmap gis data)

I tried to import a subset of open street map data to a Postgres database using the standard tool (osm2pgsql). I then tried to rebuild the indices on the table using plain sql (dropping them, then ...
3
votes
5answers
9k views

MySQL gives me:“Can't open and lock privilege tables: Table 'host' is read only”

I am facing problem restoring a MySQL database. My primary database was MySQL 5.1 and now I am trying to copy it to MySQL 5.5. The database was backed up by using Xtrabackup. I am using Ubuntu 12.04....
3
votes
1answer
6k views

Merge multiple tables in a database

I have a MySQL database with table names like 1,2,3... upto 1000 Each tables have 2000 rows and has the same structure. This is how all my 2000 table's structure look like id,url,title,content id ...
3
votes
2answers
206 views

Mongodb replica sets: why does my master server occupy more disk space than my slave?

I have two servers on my replica set. Let's call it the master and the slave, for the purpose of this discussion. The master was the original one, and the slave was replicated from that master. At ...
3
votes
4answers
4k views

pgpool replication not allowing md5 authentication

I have installed both pgpool and postgresql via apt. In pgpool.conf, I have made the changes necessary to use replication mode, as well as my two postgresql databases (currently all running on the ...
3
votes
1answer
334 views

MySQL Replication not working properly on Ubuntu Lucid Lynx Server

I have two Linux boxes. On the master following is the configuration file (my.cnf) log-bin = master-bin log-bin-index = master-bin.index binlog-do-db = test_db server-id = 1 master ...
3
votes
1answer
1k views

Problems installing Postgis extension on Ubuntu 14.04

I have Ubuntu 14.04 with Postgres 9.3 and I'm trying to install Postgis extension. One of the most recommended and straightforward ways I found is very simple: sudo apt-get install postgresql-contrib ...
3
votes
2answers
7k views

Tool for Reverse Engineering of PostgreSQL Database on Linux (Ubuntu) [closed]

Please suggest a tool to reverse engineer a PostgreSQL DB into an entity-relationship-diagram (ERD) or equivalent ?? Ideally, I'm looking for a simple ERD or UML class diagram in a format that is ...
3
votes
0answers
115 views

Recovering data from postgresql xlog

I lost a lot of data in my postgresql database and do not have a dump file to restore backup from, but I heard that in /var/lib/postgresql/9.4/main there are pg_xlog and pg_clog and that those ...
2
votes
4answers
2k views

INFORMATION_SCHEMA Selection Error

I'm trying to select data from information_schema but I'm getting the following error. How can I fix this? mysql> SELECT * FROM information_schema.tables ; ERROR 1018 (HY000): Can't read dir of '.'...