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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Is it possible to configure PostgreSQL to automatically close idle connections?

Clients connect to our PostgreSQL 8.3 database but leave the connections opened. Is it possible to configure PostgreSQL to close those connections after a certain amount of inactivity?
2
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1answer
4k views

PostgreSQL: Change default port used by utilites like psql, createdb, etc

I have 2 instances of PostgreSQL running on some servers. One on the default port (5432) and the other instance on port 5433. Some users (and processes) only need access to the second instance (5433) ...
3
votes
1answer
749 views

Retrieving queries when the hour of starting timestamp is less than the hour of ending timestamp

I have a CTE-based query in which I retrieve hourly intervals between two given timestamps. My query works as following: Getting start and end datetimes (let's say 07-13-2011 10:21:09 and 07-31-2011 ...
2
votes
1answer
344 views

What is the purpose of the keyword “ID” in PostgreSQL?

I'm new to PostgreSQL and I ran into problems using the following query: SELECT * FROM table1 WHERE ID = 1 ERROR: column "id" does not exist LINE 2: WHERE ID = 1 where ID is a column I ...
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vote
2answers
284 views

postgresql sticking “enable_seqscan=False” in a UDF sensible?

I have a query which is taking 40 seconds to execute over the 80ms that it should if postgres where to filter off the primary key rather than doing a sequential scan. I have to force postgres to ...
2
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2answers
7k views

PostgreSQL hardware reguirements

What is the memory/cpu/other requirements to run PostgreSQL database server efficiently ? Is a way to appoint a hardware configuration for some sort of requirements - for example number of users, ...
14
votes
1answer
11k views

Scalability limitations of PostgreSQL and MySQL

I've heard that performance of non-sharded relational database such as MySQL or PostgreSQL "breaks" beyond 10 TB. I suspect that limits as such do exist as one would not come up with Netezza, ...
1
vote
1answer
72 views

Deadline rule date input after now

Hi I'm trying to find a way to ensure deadlines inputted are later than the current time and date. Currently I'm attempting this with a rule. CREATE OR REPLACE RULE "DeadlineInput" AS ON INSERT ...
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2answers
2k views

Too many TIME_WAIT connections in PostgreSQL

I am using PostgreSQL 9.0 on Centos 5.7 Final. At any given there are around 1,500-2,200 connections open for PostgreSQL on port 5432 which are in TIME_WAIT state. I have a feeling this is not good. ...
2
votes
1answer
1k views

Postgresql WAL Archiving, How to do it properly?

Basically I have one (for now) mission critical postgresql database that I will need up to the minute recovery for, I've never implemented a working WAL archival before so I would like to know what is ...
5
votes
3answers
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Maximum number of databases for single instance of PostgreSQL 9

Developing a multicustomer application we plan to use a different database for each customer. But it could be more than 1000 customers (applications). Will PostgreSQL handle it without any problems? ...
2
votes
1answer
139 views

postgres 9.1: both md5 and ident on the same connection type?

In pg_hba.conf, is there a way to enable both 'ident' and 'md5' for local connections? Concretely, I am happy to have 'ident' turned on for humans to interact with the database. However, if I set up ...
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votes
4answers
13k views

Measure the size of a PostgreSQL table row

I have a PostgreSQL table. select * is very slow whereas select id is nice and quick. I think it may be that the size of the row is very large and it's taking a while to transport, or it may be some ...
6
votes
4answers
16k views

How to list all views in SQL in PostgreSQL?

How do I list all views for a database using an SQL command in PostgreSQL? I would like something similar to output of the psql \dv command, but preferably just a list of view names. e.g., SELECT ...
14
votes
2answers
4k views

PostgreSQL procedural languages - differences between PL/pgSQL and SQL

Can anybody please summarize the differences between: http://www.postgresql.org/docs/9.1/static/xfunc-sql.html and http://www.postgresql.org/docs/9.1/static/plpgsql.html ? Main points: ...
4
votes
3answers
7k views

COUNT and SUM at the same time after removing duplicate rows

I'm using PostgreSQL and I can't figure out a query for doing a COUNT and a SUM of two different columns. Basically I'm looking for something like a SUM(hits DISTINCT record_id) The table: status ...
1
vote
1answer
529 views

TimeZone parameter in postgresql.conf

postgresql documentation says: All timezone-aware dates and times are stored internally in UTC. They are converted to local time in the zone specified by the timezone configuration parameter ...
2
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4answers
10k views

What GUI tools can be used for PostgreSQL in Mac OS X? [closed]

I have recently started using PostgreSQL with my rails app. I was looking for a SQL GUI to the PostgreSQL database (for Mac). Anything better than pgadmin3?
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4answers
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How to check if a subquery has exactly one distinct result and a specified value concisely?

I found myself writing the following: select 'yes' where exists(select * from foo where val=1) and not exists(select * from foo where val<>1); and wondering if there is a more concise way ...
11
votes
1answer
7k views

How to get notices to the output stream?

I have debugging messages in functions. Those message are raised like RAISE NOTICE 'Value of id : %', id; I set my log file with \o messages.txt Then I do what I need to do with \i process.sql And ...
3
votes
1answer
578 views

Constrain input to a few different strings

Hi I can't seem to get a constraint working the way I expect in postgreSQL. From within pgadmin I execute the following SQL query. -- Check: "TypeCheck" -- ALTER TABLE "ComLog" DROP CONSTRAINT ...
5
votes
1answer
662 views

How large should my pool size be? And should I use pgbouncer?

I have a Rails application with 4 Unicorn workers. How do I determine what postgresql database pool size I should use? And if I have 6 applications connecting to this postgres database, would that be ...
12
votes
2answers
954 views

Modelling constraints on subset aggregates?

This is a cross-post from Stack Overflow. I figured I might get more interesting thoughts here. I am using PostgreSQL but I figure most of the top-end db's must have some similar capabilities, and ...
5
votes
2answers
2k views

How to force Windows to support not supported LC_COLLATE and LC_TYPE in PostgreSQL?

I have fresh installation of PostgreSQL 9.1.x. Unfortunately, I discovered that OS doesn't support LC_COLLATE = 'pl_PL.utf8' and LC_CTYPE = 'pl_PL.utf8'. I read in PostgreSQL documentation that: ...
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2answers
817 views

Postgres query plan of a UDF invocation written in pgpsql

It's possible when using the pgadmin or plsql to get a hold of a query plan for a sql statement executed via a UDF (using EXPLAIN). So, how do I get a hold of the query plan for a particular ...
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1answer
975 views

WorkAround for PHP PDO(with libpq V 9.1.4) binding for use of CITEXT?

The scenario Two systems(not server) running PHP and PostgreSQL with the following versions Fedora 15: PHP PHP 5.3.13 (cli) (built: May 9 2012 14:38:35) Copyright (c) 1997-2012 The ...
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1answer
312 views

Database for an application similar to Chatroulette

I am making an app that is similar to Chatroulette. When a user starts the app it finds someone that is not currently talking to anyone and have them talk to each other. At any point a user could ...
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votes
2answers
1k views

Pros and Cons of virtualisation technology for database-server and datastorage

Yesterday we had a chat about performance and restorability and I realized how many good things a virtualisation environment can bring to me - but as I'm a little sceptic concerning performance I'm ...
2
votes
3answers
6k views

Copy PostgreSQL data from one PC to another

I am migrating my server application from the existing system to another system. Unfortunately, the existing system is also the database server. It has data stored. Is it possible to copy this data to ...
2
votes
4answers
7k views

PostgreSQL import CSV File causes Syntax Error

I'm attempting to import a CSV file into a database via the "COPY" command; however, I get the (what seems common) error that I need to be a superuser and that I should use "\copy" instead. However, ...
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votes
1answer
5k views

disable constraints before using pg_restore.exe

When I try to execute pg_restore.exe of a dump file from a database, it throws dozens of errors, all the same: ERROR: insert or update on table "someTable" violates foreign key constraint ...
0
votes
1answer
516 views

PL/pgSQL function + client-side lo_import

I have a problem with importing documents into PostgreSQL. I have a plpgsql function, which simplified could look like this: create function add_file(flag integer, sth varchar) returns void as begin ...
1
vote
1answer
155 views

how to query for rows by specifying the range of row numbers in postgresql

I have an application where in the user can see the history of all questions he has posted. These are have to be displayed in the order newest to oldest. I am implementing this in Android. I have two ...
3
votes
2answers
422 views

Bug in PL/pgSQL function creation

I don't know if this question better suits here or in SO ... This is a script that I'd like to launch (the code of the function was copied from a question on SO): \c mydb create or replace function ...
4
votes
1answer
787 views

How to selectively replicate a PostgreSQL database

I would like to keep two PostgreSQL databases with the same schema, but have one replicated from a master that only keeps a small portion of the live data. Basically the master takes in live data ...
3
votes
2answers
5k views

PostgreSQL crash recovery

We are planning to use PostgreSQL in our application but are concerned about crash-safety and recovery. I can't find any database crash recovery method or process in PostgreSQL. I know there must be ...
1
vote
1answer
2k views

I would like to launch a pg_dump command from a remote computer

I would like to launch the command: pg_dump.exe -h 255.255.255.255 -p 5432 -U postgres -F p -a -v -f "test.db.dump" mydb from a remote computer. Both the database and the remote computer are under xp. ...
3
votes
3answers
446 views

Changing the port of the postgresql server for security reasons

For security reasons, it is common to change the port of Microsoft Sql Server. The subject is discussed here in Is changing the SQL Server port really that much safer? my question is: does this apply ...
4
votes
1answer
471 views

Can you make SSL and SSL-only (hostssl) connections to PGPool?

The new version of PGPool (3.2) has an "SSL" section in the conf file, and directions on how to use it in the manual. However, pool_hba.conf specifically says that PGPool doesn't support SSL (i.e. ...
1
vote
1answer
752 views

Create unique numeric token on PostgreSQL

I have a database where I want to generate unique tokens of six numeric characters. These tokens should be generated each time an invoice number is inserted in the invoice_no column. This would mean ...
6
votes
2answers
143 views

Can I get the union of the a Postgres fulltext index?

I have a fulltext index on a table. Is it possible to retrieve the set of terms used in the index (gist or gin)? With weights if possible? To clarify: If I have the following table: create table ...
1
vote
1answer
554 views

PostgreSQL hot standby promotion, multiple hot standbys

I'm trying to work out failover and disaster recovery procedures for a cluster of three servers. Streaming replication is being used with a high wal_keep_segments, no log shipping is happening. I need ...
12
votes
2answers
921 views

How can I generate a random bytea

I would like to be able to generate random bytea fields of arbitrary length (<1Gb) for populating test data. What is the best way of doing this?
7
votes
1answer
6k views

Starting PostgreSQL server after a HDD crash results in FAILED STATE

I am using Fedora 15 with PostgreSQL 9.1.4. Fedora crashed recently after which: An attempt to start the PostgreSQL server : service postgresql-9.1 start gives Starting postgresql-9.1 (via ...
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votes
3answers
82k views

How do I list all columns for a specified table

I'm looking for a precise piece of information in a database which I have no knowledge about. It's a 3rd party product, they are slow on answering some questions, and I know the data is lying inside ...
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votes
1answer
2k views

How to copy bytea from Postgres to Oracle

I have a db on Postgres 9.1. The db collected some binary data that are stored in bytea file. I need to copy the data to Oracle 10g. How to do it? The details I have a table plines in Postgres9.1. ...
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votes
2answers
317 views

Transfer data from database1 to database2 using task queue

We have a SQL Server legacy database, db1, to put data of Project1. With change of certain tables(insert/update) in db1, we need to transfer the changes in another postgres database, db2 (used by ...
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1answer
3k views

PostgreSQL schemas and search_path

I'm reading Oreilly's PostgreSQL: Up and Running, and in the section Organizing Your Database Using Schemas it says the search_path may be set at the database level: For example, if we wanted all ...
0
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2answers
544 views

Is there data visualisation tool for postgresql which is capable of displaying inter schema relations as well?

Operating system used is linux. I have tried Navicat and SQL Power Architect. They did display relations between tables in the same schema. I have some foreign key constraints which reference tables ...
0
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1answer
2k views

How to create a new instance of PostgresSQL on OS-X 10.8 Server

After upgrading my MacMini home server from OS-X 10.7 (Lion) Server to OS-X 10.8 (ML) + Server.app, I saw PostgreSQL 9.1.4 was released. Unfortunately, the setup process for PostgreSQL 9.1.4 has ...