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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105 views

Format timezone to +-#### instead of +-##

I am curious if there is a way to configure Postgres (9.1+) to format the TZ part of a "timestamp with time zone" as +-####, just like PHP's date.format method does using "O". PHP Docs: O | ...
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1answer
37 views

What is the impact of LC_CTYPE on a PostgreSQL database?

So, I've few Debian servers with PostgreSQL on it. Historically, those servers and PostgreSQL are localized with the Latin 9 charset and back then it was fine. Now we have to handle things like ...
8
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2answers
6k views

For absolute performance, is SUM faster or COUNT?

This relates to counting the number of records that match a certain condition, e.g. invoice amount > $100. I tend to prefer COUNT(CASE WHEN invoice_amount > 100 THEN 1 END) However, this is ...
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2answers
76 views

Return counts for multiple ranges in a single SELECT statement

I have a Postgres database table foo that, among other things, has a column for score that ranges from 0 - 10. I want a query to return the total number of scores, the number of scores between 0 and ...
1
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1answer
187 views

Postgresql memory usage [closed]

I'm trying to optimize my database (its quite heavy), I have external server only for it with 6GB RAM. I was looking for settings and saw that WORK_MEM is setted to 36MB. I thought it is possible just ...
0
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1answer
25 views

Moving PostgreSQL database to new server

I had PostgreSQL 8.3 running on a windows machine. The hard drive recently became unbootable, but the data is fine. We got a new machine and I'm re-installing Postgres. The new installer only has ...
0
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1answer
25 views

Converting hstore keys into columns in postrges

I have a database that stores a bunch of custom fields using hstore. In order to merge it into another database that doesn't support hstore, I'd like to split the keys into extra columns. Users can ...
0
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1answer
25 views

What does a CONSTRAINT have to do with my unique index?

I have to indexes on my table. The first was created by Django and the second by me. I'm not completely certain what the extra CONSTRAINT means in the first index and am wondering how I would change ...
0
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2answers
34 views

Match multiple components of a subquery CTE in PostgreSQL

I've got an app that grants access to users in varying different ways, and I'm attempting to write a query that determines access in all the different ways, but is readable, by breaking the access out ...
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0answers
23 views

Do Statement-level AFTER triggers occur asynchronously after the statement returns?

I'm using an AFTER INSERT OR DELETE OR TRUNCATE ... FOR EACH STATEMENT trigger on a table to refresh a materialized view, and I'm concerned that it will significantly affect the performance of those ...
1
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1answer
40 views

PostgreSQL - partial dump of large orbjects (pg_largeobject table)

Context : Our web-app is like a collaboration platform where you can share files, appointments, survey and so on. An instance of this web-app is divided in communities, each one is independent to each ...
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0answers
8 views

How many postgresql / BDR database can be replicated from a server? [duplicate]

I've been reading the postgresql bdr docs found here: https://wiki.postgresql.org/wiki/BDR_User_Guide I came across this comment in the above doc: BDR operates per-database, not per-cluster ...
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0answers
50 views

Centos 7, Postgresql Failed to Read Permission Data Directory in mounted Partition

I've a problem with start PostgreSQL 9.4 on Centos 7 Server. Because the partition /var/lib/pgsql/9.4/data/ (which contains PostgreSQL data) is full so I want to change to another partition. ...
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0answers
29 views

Please Help: LDAP authentication set-up over PostgreSQL

I received LDAP details and linux user details from my client. He asked me to set the LDAP over PostgreSQL. when i did so i am getting error: "invalid authentication method "ldap": not supported by ...
0
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1answer
103 views

mongodb on-premise: will it work?

We are planning to package MongoDB-PostgreSQL hybrid solution in our application that will be deployed on customer site on-premise. It will be packaged as a software virtual appliance. Our reason for ...
1
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1answer
49 views

Grouping() equivalent in PostgreSQL?

I have a SQL query that runs in MS SQL Server and it has grouping(), rank() and rollup() functions / keywords in it. The query is given below. How can this be translated to PostgreSQL? select top ...
1
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1answer
30 views

How to measure or estimate the streaming replication lag in Postgres 9.2

I've been asked to reverse engineer an app that uses postgresql in the back end. I can see that there is some database replica tion going on... based on my reading, I *think it's called streaming ...
0
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0answers
58 views

postgresql 9.4 + BDR Fails

I'm trying to get postgresql 9.4 and BDR working. Following this tutorial: https://wiki.postgresql.org/wiki/BDR_Quick_Start Actually, my sysadmin provided me with a package to test with. He's taken ...
0
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1answer
22 views

COMMIT after EXPLAIN ANALYZE of a read-only query

In PostgreSQL, what effect could produce issuing a COMMIT after executing an EXPLAIN ANALYZE with a read-only query?
2
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1answer
34 views

Operator “~<~” uses varchar_pattern_ops index while normal ORDER BY clause doesn't?

Let's say I have a table with 1 000 000 records. Structure of table is: create table individual ( id serial primary key, surname varchar(128), "name" varchar(128), patronymic ...
2
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0answers
35 views

Execution plan of query inside pl/pgsql function

Briefly, we have a pl/pgsql function which collects some intermediate data in several temporary tables ("on commit drop") and then returns REFCURSOR which joins those temporary tables with some static ...
0
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1answer
20 views

Can an active Postgres serverlog be truncated?

Running Postgres 9.1 on Ubuntu 14.10 LTS. I've got an application running on a machine that's going to run out of diskspace soon. However, the application is in the middle of a crucial run that has ...
2
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1answer
97 views

PostGIS: Cutting Holes in Self Geometry

I have a table of geometries in PostGIS, some of which overlap. When I display the geometries, this has the unfortunate consequence of blending the two stacked geometries together and producing an ...
20
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4answers
8k views

PostgreSQL Stored Procedure Performance

Coming from a MySQL background, where stored procedure performance (older article) and usability are questionable, I am evaluating PostgreSQL for a new product for my company. One of the things I ...
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3answers
2k views

Streaming Replication in PostgreSQL

I'm trying to set up two PostgreSQL servers on one machine and perform a streaming replication. I have succeeded once, but when i've tried again following exactly the same steps it doesn't work.. ...
0
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1answer
50 views

Postgresql - Minor version upgrade 9.3.5 to 9.3.6 on Ubuntu

I am two servers: A & B. My master database is running on A and the version is 9.3.5. It's replica is running on B and the version is 9.3.6. I am trying to use B as UPSTREAM slave, and trying to ...
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1answer
41 views

Create/copy new superuser from an existing one

I have a superuser for a PostgreSQL database, let's call him userX. How can I make a new superuser (let's call him userY) with all the same permissions, access, etc...? Basically, I want a clone of ...
0
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1answer
41 views

hstore type does not exist with hstore installed postgresql

I recently had to copy over a databases structure from one database to another with the command pg_dump -c -S database_name > pg_dump_date.sql I then ran the dump file on the new database with ...
3
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2answers
761 views

Slow queries on billions-rows-table // index used

Since I'm a young developer and not really skilled in using databases (PostgreSQL 9.3) I ran into some problems with a project, where I really need help with. My project is about collecting data of ...
0
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1answer
86 views

Pros and cons of using many schemas in PostgreSQL as opposed to just one?

For a large SAAS application (backed by PostgreSql 9.4), with over 300,000 accounts (and growing), what are the pros and cons of using a schema per account to partition the data vs putting all the ...
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2answers
31 views

Calculating the number of times a motive was cited over a given period

I'm using PostgreSQL 9.4. I have the following surveys table. Each row includes a motive that was cited by the respondent, represented by the motive_value column (think of it as motive_id). ...
1
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1answer
37 views

Delete array element by index

Is it possible to delete a Postgres array element by index? (Using Postgres 9.3.) I don't see anything for this in the docs (http://www.postgresql.org/docs/9.3/static/functions-array.html) but ...
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2answers
1k views

Select longest continuous sequence

I am trying to construct a query in PostgreSQL 9.0 that gets the longest sequence of continuous rows for a specifc field. Consider the following table: lap_id (Serial), lap_no (int), car_type ...
0
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1answer
116 views

Implementing Permissions Database structure on a PHP site to restrict the Access in Multiple levels

I am working on a PHP site that shows the business of a Vehicle Showroom company in which we have 3 users as, Admin(Owner) = Here Admin Have all Access by default(View,Edit,Delete to all) Super ...
1
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2answers
64 views

Combine results of two queries, where the second relies on the first

I have one query which is returning name(text), total, created_at And another query which is returning the same thing name(text), total, created_at The second query usually is returning more ...
0
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2answers
117 views

Schema for lists of relationship differences

Say there is a data model that allows for relationships to be defined either explicitly or as a list of records added or removed relative to some existing item: Item <–> *Properties and Item ...
0
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0answers
26 views

Integrating Postgres/GIS data in a SQL Server environment without generating 'data islands'

Currently I'm facing a scenario in which a GIS expert is planning on starting to integrate mapping services for several departments within the organization I work for. I handle around 40 mid-sized ...
1
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1answer
117 views

Partial unique constraint spanning multiple tables in postgres

To enforce partial uniqueness in postgres, it is a well known workaround to create a partial unique index instead of an explicit constraint, like so: CREATE TABLE possession ( possession_id serial ...
1
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1answer
104 views

How to design tables for airbnb style booking system

all. My English is not very good, but I will try to describe my question as clear as possible. I want to design a airbnb(https://www.airbnb.com) style booking system, this kind of booking system ...
0
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3answers
41 views

Group by transformed column

I have a database with creations and orders, and a bunch of tables linking them. I want to extract, for each month, the number of ordered creations, and the sum of amount for these orders, but for a ...
0
votes
1answer
355 views

pgpool2 not working on my Ubuntu i686 athlon i386 GNU/Linux

I am trying to implement replication and load balancing on my Ubuntu i686 athlon i386 GNU/Linux.for creating database clustures I have installed postgresql contrib 9.1.11 having initially database ...
2
votes
1answer
72 views

Can bdr only replicate one database per server?

I have installed the new BDR-Solution with PostgreSQL 9.4 and it works like a charm. My Problem: I want to add more databases to the replication but every time if I added the other database and ...
0
votes
1answer
99 views

Postgres automatic failover, multiple clients to multiple masters

I'm looking into providing a method of having multiple hot spare PostgreSQL instances to our website. The majority of implementations that I have found require a single point of failure with PgPool ...
0
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1answer
31 views

Get table name by foreign key

I have a two tables in the database. First table has a foreign key to second table. Can I get second table name by the foreign key from first table?
1
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2answers
45 views

Combine multiple similar queries into one

I need to calculate a weighted average using the following table. I have to calculate this number for metric_1 up to metric_10. All the metric columns have a value from 1 to 5. ...
1
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0answers
27 views

Postgres configuration, incoming connections

Hello I'm trying to figure out the best way to allow connection from certain ips/hosts to my db instance. I've got an api(s) pointing to the database and right now we do something like this ...
0
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1answer
53 views

How to avoid duplications using a function

I am using this function in a bulk insert to avoid duplication of url paths. CREATE OR REPLACE FUNCTION "univ"."gc_landing"(IN _name text, OUT landing_id int4) RETURNS "int4" AS $BODY$ DECLARE ...
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0answers
28 views

How can I tell which client process owns a particular Unix domain socket connection?

I recently tried to call ALTER TABLE, which got blocked because one of the transactions holds a lock on the related table. With the help of #postgresql IRC channel, I managed to track down the problem ...
0
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2answers
97 views

PostgreSQL : dependencies on a schema

I need to delete a schema in my PostgreSQL database. I would like to make sure that the schema is not used in another schema (for instance : this schema is used for a view in another one). Is there a ...
0
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1answer
83 views

Pgpool II : unable to read message length between two network interfaces

Start log file: 2015-03-06 01:57:56: pid 2760: LOG: Setting up socket for 0.0.0.0:9999 2015-03-06 01:57:56: pid 2760: LOG: Setting up socket for :::9999 2015-03-06 01:57:56: pid 2760: LOG: ...