PostgreSQL is an enterprise class, open-source, object-relational database management system (ORDBMS) available for all major platforms including Linux, UNIX, Windows and OS X. Please mention your exact PostgreSQL version when asking questions.

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Save output from multiple SQL SELECT commands to a file

Within a Postgres function I would like to run a number of SQL SELECT commands and append the output to the same variable. After all the SELECT commands have run this output should be written to a ...
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2answers
430 views

Database Restoration Issue

I am new with postgresql. When I attempt to restore database a .sql.gz file into the database with psql, the restore does not complete when the database size is too large (32Gb, for example). These ...
2
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1answer
176 views

PostgreSQL replication

I have two projects working on different databases. The problem is: I need to replicate changes in the databases only for a few tables. I need it to synchronize the data. Need an advice how can I ...
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2answers
182 views

Performance of different precedence pseudocolumn solutions with LIMIT

I was wondering about the relative performance of the solutions provided in the answers to a question on stackoverflow, I decided to run some tests. The OP wanted to get the first matching row given ...
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2answers
1k views

ERROR: could not find array type for datatype information_schema.sql_identifier

I am trying to run the below sql command: SELECT ARRAY( SELECT column_name FROM information_schema.columns WHERE table_name ='gis_field_configuration_stage' ); and I get the below ...
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1answer
568 views

Execution plan in simple query in PgSQL depends on offset clause, why?

Update on 2013-01-16 11:08: see below I am working on PostgreSQL 8.4.14 with the following table fed with 53k lines: CREATE TABLE botany.taxon_data_cache ( taxon_id int NOT NULL, ...
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1answer
376 views

MAX function and group by usage - postgresql

I am building a ranking algorithm using IMDB's formula: http://stackoverflow.com/questions/1411199/what-is-a-better-way-to-sort-by-a-5-star-rating/1411268#1411268 The formula for calculating the Top ...
0
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1answer
270 views

Storing 5TB web server access log vs OLAP DB

We have over 5TB compressed web server log in a HDFS and we often analyse using Hadoop. It is painful to run map reduce on 5TB of data and most importantly, not many developer are familiar with it. ...
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1answer
2k views

PostgreSQL pg_stat_activity shows COMMIT

We recently replaced our database server with an upgraded machine with 4 x quad core CPUs and 32Gb of ram. We also repurposed our old box to serve as a slave with streaming replication. Both boxes are ...
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1answer
4k views

Retrieving data from inner join using LIMIT and OFFSET

These are my two tables: table1 qid[PK] |gid[PK] |abcd | xyz | date ---------------+---------+---------+------+------------ 00001 | qwe | 54 | a | 1994-11-29 00002 ...
3
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1answer
434 views

Comparing table structure and contents using pg_dump output from two different databases

If I have the output of pg_dump from two different databases, how can I get the difference in structure and contents of all the tables between these two databases?
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1answer
351 views

Optimal PostgreSQL setup for Windows 2008 R2

I have PostgreSQL 9.2 setup on Windows 2008 R2 64bit with 96 gigs of RAM and 8 cores. What would the optimal settings be for shared_buffers, effective_cache_size, work_mem, etc.? I realize that these ...
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1answer
687 views

pg_hba.conf from PostgreSQL

I have no idea how to configure that pg_hba.conf file, to connect with my server via pgAdmin. Right now i was trying to add: host all all host.name.org.pl trust host all all host.name.org.pl md5 ...
2
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1answer
309 views

sorting groups of related rows by average values while keeping the groups together

I'm using PostgreSQL 8.4, but would like a standard SQL solution if possible. Consider the following table. corrmodel=# SELECT * from data limit 1; id | datasubgroup_id | datafile_id | ...
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1answer
260 views

PostgreSQL: how can queries possibly be “immutable” / functional?

I've read that PostgreSQL can have "functional" indexes. For that you need the immutable keyword. Seen that PostgreSQL is a CRUD DB I don't understand at all how it can possibly work in a functional ...
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2answers
795 views

inet_client_addr in PostgreSQL don't return IP

i trying use the function inet_client_addr() (PostgreSQL 9.2) in a trigger, but the return is '::1/128'. This is a problem with my script or with the server? CREATE OR REPLACE FUNCTION ...
4
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2answers
1k views

How do I know what indexes to create for a table

Is there a way I can figure out the best way to know which indexes to create for a table?
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2answers
508 views

Database Design - One table from many source(One to One)

I have a 'Text' table, the text table may came from different source, like Tweet, SMS, Email, etc. and each source have their own log, and Text is came from the source. so i came with some solution, ...
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1answer
750 views

Equality query on NVARCHAR column yields multiple results in SQL Server 2012

I am in the process of moving a pet project from PostgreSQL (9.2.2) to SQL Server (2012 Standard). I've noticed an interesting phenomenon when querying unicode words. Given the definition: CREATE ...
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1answer
577 views

PostgreSQL: Recommendation size for shared_buffers

I am rather new to PostgreSQL. I started migrating some MySQL databases to PostgreSQL one month ago. I am looking for help about the proper memory values for the configuration file. Currently, I ...
4
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3answers
267 views

How to prevent query execution after exiting the \e editor in psql?

Is there an option that can change the "exit external editor -> query runs automatically" behaviour of the psql \e switch ? (Other than intentionally mangling the query syntax).
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1answer
555 views

Is there a recommended way to update a database schema when updating and app's RPMs?

I have a pretty standard server layout: 2 Application servers running Tomcat on Redhat. 2 Database servers running Postgres on Redhat. One database is a master and replicates to the slave. I'd ...
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1answer
1k views

How does Postgres 9.2's streaming replication handle schema changes, and initial table setup?

I want to set up a backup database on the physical server which sits right under my primary physical database server. I'm using Postgres 9.2, and I want to use synchronous, streaming replication (for ...
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1answer
293 views

PostgreSQL Return Joined Results of Select

I'm learning PostgreSQL and was wondering if I can put long selects in stored procedures like this one: CREATE OR REPLACE FUNCTION api.book_list() RETURNS TABLE ( id BIGINT, published ...
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1answer
595 views

PostgreSQL - using password/md5 authentication with empty password

I have the following role in my system: CREATE ROLE test LOGIN INHERIT NOCREATEDB NOCREATEROLE NOREPLICATION; There is no password. Trying to connect to the db from within the same machine using ...
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2answers
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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 ...
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2answers
221 views

Custom Postgres function not working

I wrote this function that is supposed to iterate through a text array and convert each element (which is a typecasted integer) to hex, append to a text variable, then return the hex. However, I get ...
2
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1answer
662 views

Lost postgreSQL password in Windows installation

I have postgresql 9.2 installed on a windows XP machine. I have lost the postgres password. I looked at answers given to a similar question asked 6 months ago. The answer given there required the ...
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1answer
2k views

libreadline.so.6

when I was installing PostgreSQL from source code I had to install the libreadline.so.6 library. From that moment I can't update my kubuntu system. The error is: Setting up ubuntu-keyring ...
2
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1answer
183 views

Which database to use? [closed]

Hey there. I am looking for a free to use for commercial website database that should have these design features, in the given order: Auto-Sharding (getting more free space by adding more server ...
3
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1answer
1k views

SET extra_float_digits = 3

I'm using postgresql 9.2 with my web application that has three servlet with three select. I turn on the log. When i send my first query: 'select * from "Nomi" limit 4' before this the log show me ...
5
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1answer
4k views

ERROR: database “dbname” does not exist

According to the documentation, so long as I'm not connected to a database, I can either delete a database in the console using: DROP DATABASE dbname; Or I can drop it using the wrapper tool ...
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1answer
68 views

PostgresSQL: Cannot get to console under different user name

I normally get to the console in UBUNTU by typing: sudo -u postgres psql But I need to delete a database owned by a different user. When I type: sudo -u username psql It tells me "database ...
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2answers
663 views

How do I solve an error code 127 when doing a pg_dumpall through a cronjob?

I have this simple script to backup all my databases in postgres pg_dumpall -U pg_user > /tmp/tmp.txt DUMP_STATUS=$? echo "Dump status: $DUMP_STATUS" > /tmp/status.txt The dump ...
5
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1answer
4k views

pg_dump and ERROR: missing chunk number 0 for toast value

I'm using PostgreSQL 8.4.15. While running pg_dump to backup a database, I got the following error: pg_dump: SQL command failed pg_dump: Error message from server: ERROR: missing chunk number 0 for ...
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3answers
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Postgresql 9.2 won't start after rerunning installer

All, I made a fatal mistake and accidentally ran the core installer for postgresql rather than the stackinstaller. I didn't go all the way through the install process but it still set something that ...
0
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1answer
325 views

Why doesn't more memory necessarily make Postgres more performant?

The Postgres resource consumption docs state, under the shared_buffers: ...it is unlikely that an allocation of more than 40% of RAM to shared_buffers will work better than a smaller amount. Why ...
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3answers
4k views

Computer restarted and Postgres 9.2 service cannot be started?

My firewall is down and when I tried to start the Postgres service it gave me an error that said: the service started and then stopped. Some services stop automatically if they are not in use by other ...
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5answers
6k views

Best cloud platform for PostgreSQL [closed]

Currently, in our project, we use dedicated servers for our PostgreSQL database. In theory, we can run anything on some cloud platforms. However, PostgreSQL configuration is strictly related to ...
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2answers
10k views

Connect to Postgresql 9.2 from Eclipse Data Tools Platform

GOAL: My goal is to write sql code within Eclipse to query a Postgresql database. The reason I want to write my queries within Eclipse is to then write R or Python code to perform statistical analysis ...
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4answers
1k views

Backup a sample of a PostgreSQL database

Is it possible to back up a PostgreSQL database with only a fraction of the data (1000 Rows from each table)? I am able to back up that database using pg_dump. In some case I need db with minimum ...
3
votes
1answer
229 views

Bayesian ranking

I have the following table in my database: ╔════════╦═════════════╦═══════════════╗ ║ Name ║ total_stars ║ total_reviews ║ ╠════════╬═════════════╬═══════════════╣ ║ Item A ║ 27 ║ ...
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3answers
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“AT TIME ZONE” with zone name PostgreSQL bug?

I was answering this stackoverflow question and found strange result: select * from pg_timezone_names where name = 'Europe/Berlin' ; name | abbrev | utc_offset | is_dst ...
4
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1answer
131 views

Postgresql, write archive file over mount, secure against simultaneous access?

I am using Postgres 9.2.1 and am saving my archivable WAL over a NFS share. I just use the basic command, given as an example in the postgresql.conf test ! -f /mnt/server/archivedir/%f && cp ...
6
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1answer
356 views

Privileges required to install PostgreSQL

I am new to PostgreSQL Database. I need to install it in my machine. I am not administrator in my system. Can some one suggest, if Non-Administrator can install it. If there is any other way of ...
4
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1answer
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Postgres scalability - What is the impact of connection pooling?

We had a question over on Server Fault that raised an interesting question: In light of the scalability improvements in Postgres 9.2 scalability improvements, is it better to use connection pooling ...
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1answer
221 views

Parse hyphenated word to unsigned integer

When tested to_tsvector on 'someword-123' with english full text config, I got the following result: SELECT to_tsvector('someword-123'); to_tsvector tsvector -------------------- "'-123':2 ...
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4answers
3k views

Cannot shutdown old postmaster when upgrading to Postgres 9.2

I'm upgrading to Postgres 9.2.2 (from 9.1.4). When I try to upgrade the DBs using: pg_upgrade -b /usr/local/Cellar/postgresql/9.1.4/bin -B /usr/local/Cellar/postgresql/9.2.2/bin -d ...
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2answers
3k views

Running pg_dump on a hot standby server?

Disclaimer: I admittedly haven't tried this yet, but I'm not sure I would know if it wasn't working correctly, so I wanted to ask. I would like to run a nightly backup job (via pg_dumpall) from a hot ...
10
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2answers
2k views

PostgreSQL: Can I do pg_start_backup() on a live, running db under load?

Our established replication has broken ("requested WAL segment has already been removed" during downtime) We cannot easily stop the master again. Can we do pg_start_backup(), rsync ${PGDATA}/ ...