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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2
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1answer
89 views

PL/pgSQL function or rCTE to detect depth of relations between two tables

I need to perform a PostgreSQL Function for checking the depth of relations. There is a circular binding from table a to b, back to another element in a and, in some cases back again to b. These ...
2
votes
3answers
1k views

Postgresql: datatype for email address

What would be the right datatype to store email addresses in PostgreSQL? I can use varchar (or even text), but I wonder if there is a more specific data type for emails.
4
votes
4answers
4k views

Passing arguments to psql

I'm running a plpgsql script in Postgres 8.3 - I would like to pass arguments to this script via psql. I'm currently executing the script like: psql -d database -u user -f update_file.sql I came ...
7
votes
2answers
11k views

PostgreSQL 9.1 Hot Backup Error: the database system is starting up

I have been working on a hot backup for Postgres 9.1 for awhile and have run into a consistent issue. After restarting Postgres on the slave server the pgstartup log file and the daily log file under ...
2
votes
1answer
145 views

Searching a big table for a few results without scanning the whole table

I need to search a very big PostgreSQL table (500+M rows), I want to limit the returned search results, but using the "limit" keyword cant prevent the search over the whole set of data(is it correct?) ...
2
votes
2answers
373 views

SELECT UNION from two views of the same table

(Sorry the the vague title, if anyone want to re-edit, be my guest!) I have these tables and views for a factory inventory module : +----------------------------+ +--------------------------+ | ...
1
vote
1answer
77 views

Update different columns on different clauses

I have a database table in Postgres 9.3 with the following layout: id SERIAL, col1 INT, col2 INT Whenever a new row is inserted, I will have to update ALL rows col1 and/or col2 in different cases ...
6
votes
2answers
120 views

How can I fake inet_client_addr() for unit tests in PostgreSQL?

I have a simple stored procedure whose return value depends on the value of inet_client_addr(). How can I override inet_client_addr() for the purpose of unit tests when testing my stored procedure? ...
2
votes
1answer
121 views

How to determine if postgres database contains GiST indexes and what type?

Is there a way to easily check if a PostgreSQL database has any GiST indexes and of what type they are?
1
vote
1answer
432 views

Grant usage partially on schema to user on Postgres

I granted INSERT in a specific table for one user. The problem is that I need to also grant USAGE in the schema for this same user, but granting USAGE in schema also turn all relations in that schema ...
1
vote
1answer
531 views

PostgreSQL Slave has more files in pg_xlog than /wal_archive

Background: for various reasons I am switching PostgreSQL Slave from a Streaming replication to a warm standby replication. The streaming replication was setup using this guide: ...
0
votes
0answers
150 views

cascade delete doesn't work even though constraint is added

I created the following table: CREATE TABLE message_link ( id serial NOT NULL, thread_id integer, message_id integer, user_id integer, read boolean NOT NULL, CONSTRAINT message_link_pkey ...
0
votes
1answer
119 views

PostgreSQL synchronous replication time out?

I'm using PostgreSQL 9.3 with synchronous replication. I have 2 synchronous replicators and 1 async replicator. My problem is when 2 synchronous replicators are down, transaction will wait ...
0
votes
2answers
91 views

How can I make this query more efficient?

This is the query: SELECT races.*, tmptimers.last_start_time, tmplaps.updated_at AS last_updated_at FROM races LEFT JOIN (SELECT * FROM timers WHERE timers.user_id = 1) AS tmptimers ON ...
0
votes
0answers
37 views

Which primary keys must be specified when using slony PostgreSQL replication?

I'm extremely green when it comes to databases, so forgive my ignorance. I've been researching ways to replicate our production Postgres DB, and I've decided to try out Slony. Since the server is ...
1
vote
1answer
72 views

How to optimize multiple ORDER BYs?

I'm getting sluggish performance on a table with ~300,000 rows and B-Trees on each column. This is for a dynamic pagination page where the query is constructed on demand, and the application caches ...
0
votes
0answers
105 views

Understanding correct procedure to recover master in master-slave replication in PostgreSQL

For learning, I have setup master-slave streaming synchronous replication. Pg-pool 3.3.3 is installed in one VM and it connect to 4 VMs which runs PostgreSQL 9.3, one master and 3 slaves. Replication ...
8
votes
3answers
26k views

How to solve UTF8 invalid byte sequence copy errors on a restore, when the source database is encoded in UTF8?

I was given the task to migrate a PostgreSQL 8.2.x database to another server. To do this I'm using the pgAdmin 1.12.2 (on Ubuntu 11.04 by the way) and using the Backup and Restore using the ...
1
vote
1answer
69 views

how to update the value of a period contained inside a bigger range

I have a tsrange like '[2010-01-01 14:00, 2010-01-01 15:00]',20 And want to update the 20 value to 15 in a range inside that, like '[2010-01-01 14:10, 2010-01-01 14:30]',15 My expected outcome ...
0
votes
1answer
25 views

Migrating a database from one PostgresSQL server to another cleanly

I have a Rails app server that uses Postgres for the db backend. I'm spinning up a new server and I want to get a clean and up to date copy of the database. I've tried it once so far while the ...
3
votes
1answer
162 views

PostgreSQL: Trigger for updating view doesn't work

I'm trying to make the trigger for updating a view work. If I'm doing and INSERT it works! But when I'm trying to do an UPDATE it just doesn't run. CREATE OR REPLACE FUNCTION test_trigger_function() ...
0
votes
1answer
73 views

Does PostgreSQL take time to start streaming replication after restart master?

I set streaming replication in postgresql 9.3. I have one master and 3 slaves and replication works fine. But when i restart the master server and login using postgres database, pg_stat_replication ...
0
votes
1answer
51 views

Unmount/detach/deactivate PostgreSQL database

I manage a server that serves several web applications that use PostgreSQL as a data store. Each web application has a separate role and database, and each database is stored exclusively on a ...
1
vote
1answer
85 views

Calculate value differences of rows before and after bounded by multiple referenced rows

Supposed I have a user travelling table like this: id | start_time | end_time | location | ----+--------------+------------+------------+ 1 | 1 | 2 | Loc_A | 1 | ...
7
votes
3answers
4k views

What can I do with the new json field?

PostgreSQL 9.2 introduced the json field type. Why and when should I use it? What benefits does it have over a text field? I thought there were new query options available, however I haven't seen ...
2
votes
1answer
538 views

PostgreSQL streaming versus file-based replication (In terms of server behavior & configuration)

I am trying to understand best uses of PostgreSQL replication and how it works so I can troubleshoot in a production environment. I am having a hard time understanding the differences between these 2 ...
1
vote
1answer
49 views

Optimizing bulk update performance in Postgresql with dependencies

Basically my question is the same as this one, but WITH dependencies, so drop/renaming the table is not a trivial option (I assume). We are refactoring a large, poorly designed table which has many ...
1
vote
1answer
168 views

PosgreSQL: very slow select on a single table with no joins

I'm trying to help a colleague who's having some problems with a PostgreSQL query. We've narrowed it down to a join to one table making the query painfully slow and, upon investigation, we found that ...
0
votes
2answers
213 views

SUM() the result of a stored procedure

I use the Pl/Proxy extension in order to shard a table. It works like a charm, except for this : I have a stored procedure which runs on 4 shards. It looks like this : CREATE OR REPLACE FUNCTION ...
5
votes
4answers
8k views

Select COUNT of days between two dates except weekends

I am trying to get the number of days between two different dates, except the weekends. I don't know how to achieve this result.
0
votes
0answers
65 views

Matching array values in PostgreSQL with ActiveRecord

In my Rails 4 app I have a goal to see all contacts, where field visible_to in contacts table equal to 1. My visible_to is :integer, array: true. However, I get the following exception: ...
3
votes
1answer
38 views

Why does the behavior of array syntax differ from '(?,?)' syntax when updating a point field and that field is NULL?

I'm using PostgreSQL 9.3.5. Suppose I have the following table: CREATE TEMPORARY TABLE point_test ("name" varchar(255), "pt" point); I then insert a row, leaving pt NULL: INSERT INTO point_test ...
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vote
0answers
70 views

Importing PostgreSQL backup into slightly different database

I have a pg_dump backup which represents a slightly older version of a client dataset. A newer schema is running on the client's production environment, and there is not a readily available tool to ...
0
votes
1answer
97 views

Connect Jira to Postgresql with Pgpool-II

I gotta problem with connecting Jira 6 to Pgpool-II which is responsible for load balancing and replication in Postgresql bases(2 instances). Pgpool is started on port 9999, I just want to connect ...
1
vote
1answer
447 views

Postgresql: Difference between pg_dump and backup/restore?

Don't they essentially do the same thing by storing all the data in a file and dumping it into another database? Is it that pg_dump just adds the data on to whatever is already there and restore ...
2
votes
1answer
487 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 ...
7
votes
2answers
4k views

How can I update a json element in postgresql json datatype

I can't figure how can I update an element in a postgresql 9.3 datatype. My exemple the db CREATE TABLE "user" ( id uuid NOT NULL, password character varying(255), profiles json, gender ...
3
votes
1answer
77 views

Postgresql query plan differs with limit value making the query slower for lower limits

I have this query: SELECT "table_1".* FROM "table_1" WHERE "table_1"."deleted_at" IS NULL AND "table_1"."table_2_id" = 15797104 ORDER BY "table_1"."id" ASC LIMIT 1 The explain for the query ...
0
votes
1answer
87 views

Postgresql Chained Slaves and Slave Promotion

So I have a setup like Master -> Slave1 -> Slave2. Slave1 replicates from Master and Slave2 replicates from Slave1. If I promote Slave1 to master is it possible for Slave2 to continue replicating from ...
1
vote
1answer
54 views

Does PostgreSQL allow multiple grantees in GRANT commands?

Looking at the PostgreSQL docs it seems that the GRANT command only grants to a single user or role. In fact it doesn't seem to be PostgreSQL alone. Isn't possible to do something like GRANT SELECT ...
0
votes
0answers
52 views

Bulk update performance

I have a several process that aggregate some statistics on items (how much was shown, clicked ... around 30 factors). Once in a 5 minutes i flush the aggregate data to postgres (9.1). I have 250K ...
2
votes
1answer
438 views

Create a new table (multiple columns) by selecting random values from an existing table

I am stuck on the following task (PostgreSQL 9.3). Let's say we have the following table1 (which has 10k rows): table1: id 754 800 330 4 59 My goal is to create another table2 with two columns ...
1
vote
1answer
56 views

restoring Postgres dump with tablespaces

I'm trying to restore a dump done with pg_dumpall > mybak.sql from a server that has 1 table in a different tablespace that the default one. On the target machine I have recreated the directory ...
2
votes
1answer
926 views

MS SQL - export tables to format compatible with PostgreSQL

We're using MS SQL Server 2005 at work and I want to export our data to PostgreSQL for testing. MS SQL Server has an export function but the only one that looks like it would work would be to export ...
1
vote
1answer
144 views

Paritioning performance for full table scan on non-paritioned index

We have a table in Postgres that we are considering partitioning. We occasionally query an indexed field that is separate from one with the partition key. My question is: Can partitioning the table ...
3
votes
4answers
294 views

psql, getting a list of databases to be parsed by a script

I want to use psql to list all of the databases on a Postgres server, to be parsed by a script. This command lists them: psql -l -A -t but the output shows an obvious issue: the records are ...
0
votes
1answer
90 views

How do I list all databases and tables using psql in a pipable format? [duplicate]

This question deals with getting a list. So I get this: $ psql --list List of databases Name | Owner | Encoding | Collate | Ctype | ...
0
votes
1answer
525 views

group by clause without aggregate function

I've always assumed GROUP BY was designed specifically for aggregate functions and in all other circumstances you should use ORDER BY. For example, we have three tables: orders, shippers, and ...
1
vote
0answers
61 views

upgrading from Postgresql 9.1 to 9.3 on Ubuntu using Londiste

I am undertaking a project to upgrade our Postgresql production database from 9.1 to 9.3 using Londiste. The reason I choose Londiste is to avoid substantial downtime from restoring the dump file or ...
7
votes
0answers
229 views

How to handle bad query plan caused by exact equality on range type?

I'm performing an update where I require an exact equality on a tstzrange variable. ~1M rows are modified, and the query takes ~13 minutes. The result of EXPLAIN ANALYZE can be seen here, and the ...