PostgreSQL is a powerful, enterprise class, open source RDBMS. It has more than 15 years of active development and a proven architecture that has earned it a strong reputation for reliability and data integrity. It runs on all major operating systems, including Linux, UNIX and Windows. It prides ...

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5
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2answers
1k views

Postgresql 8.3: Limit resource consumption per query

I'm using PostgreSQL 8.3+PostGIS 1.3 to store geospatial data on Ubuntu 8.04 Hardy. This particular version of PostGIS has a bug when calculating a buffer() on very complex segments, which causes ...
4
votes
1answer
121 views

Optimizing concurrent updates in Postgres

I'm running concurrent Postgres queries like this: UPDATE foo SET bar = bar + 1 WHERE baz = 1234 Each query affects the fixed K number of rows, and I can't find a way to enforce the order in which ...
4
votes
1answer
257 views

How to apply a patch in PostgreSQL on Windows?

How to apply a patch in PostgreSQL? I found an advice, but it seems to be suited for *NIX only. My PostgreSQL (9.3.1 EDIT: 9.3.4 now) was installed from an exe installer on Windows XP (32 bit), so I ...
4
votes
1answer
126 views

Order by distance

If I have a query returning nearby cafes: SELECT * FROM cafes c WHERE ( ST_DWithin( ST_GeographyFromText( 'SRID=4326;POINT(' || c.longitude || ' ' || c.latitude || ')' ), ...
4
votes
2answers
255 views

Order of columns in a compound index in PostgreSQL (and query order)

I have a table with 50K rows. It is actually a PostGIS table. The query has 4 parts (1 mandatory) (3 Optional) intersection box (a geography rectangle) with 4 lat,long (I use st_intersects) ...
4
votes
2answers
1k views

PostgreSQL CREATE TABLE creates with incorrect owner

I'm using PostgreSQL 9.2.4. When I create a table as a non-superuser in a database owned by that non-superuser, it is owned by the postgres user, so I can't put any data into it unless I explicitly ...
4
votes
1answer
960 views

How do I get the aggregate of a window function in Postgres?

I have a table containing a two columns of permutations/combinations of integer arrays, and a third column containing a value, like so: CREATE TABLE foo ( perm integer[] NOT NULL, combo integer[] ...
4
votes
3answers
706 views

Is a REINDEX required after CLUSTER?

I'm considering using CLUSTER to reorder a table by an index. I understand that this recreation of the table data makes all the existing indexes either bloat or be useless. I've seen some indications ...
4
votes
2answers
420 views

How to wait for PostgreSQL to be startable / restorable?

I'm testing a PostgreSQL 8.2.1 to 9.2 upgrade on a virtual machine running a custom Linux distro. The upgrade procedure is as follows: Start the pg service Vacuum all DBs (not sure if this is ...
4
votes
2answers
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
1answer
3k views

What is the meaning of n_live_tup and n_dead_tup in pg_stat_user_tables

What is the meaning of n_live_tup and n_dead_tup in pg_stat_user_tables or pgstattuple?
3
votes
3answers
208 views

Join table on some conditions

I've got a table called activities. And a table messages. Activity has many messages, and one message has one activity. This are the message columns : id sender_id receiver_id body activity_id I'm ...
3
votes
2answers
111 views

Compound Index on 43 Million PostgreSQL table

This question is related to a prior one of I asked: Order of columns in a compound index in PostgreSQL (and query order) Rather than overload that question, I figure I can sharpen and limit my ...
3
votes
1answer
2k views

Fixing table structure to avoid `Error: duplicate key value violates unique constraint`

I have a table which is created this way: -- -- Table: #__content -- CREATE TABLE "jos_content" ( "id" serial NOT NULL, "asset_id" bigint DEFAULT 0 NOT NULL, ... "xreference" varchar(50) ...
3
votes
1answer
74 views

Use of integer instead of interval (of one type)

Our DB design presently has a interval column which will only be storing days (no other interval type) so it is making sense to use INT2 (smallint) instead of interval. Reference to documentation. ...
3
votes
2answers
983 views

Do all users need access to the postgres database in pg_hba.conf?

I was just testing the user creation process in pgAdmin. I have a database db1 for which I want to create a user to be able to connect to it. I want this to be the only database the user can connect ...
3
votes
1answer
418 views

querying a linked PostgreSQL database in SQL Server 2008

We will be deploying an application with a Postgres back-end and need to provide report writing capabilities in SQL Server. I am exploring options for real-time or near real-time reporting in this ...
3
votes
1answer
77 views

PostgreSQL + query planner + amount of entities

I'm working on college work about how query planner uses statistics and makes the most optimal query. I have read the 57.1. Row Estimation Examples article and I know how's the PostgreSQL calculates ...
3
votes
1answer
2k views

postgres and passwordless authentication

We have users for out postgres database and none have passwords... Do not know the history behind it. When I try to use clients to connect to these databases, for instance, pgadmin III, the ...
3
votes
1answer
9k views

How can I convert from Double Precision to Bigint with PostgreSQL?

I need to convert a value of Double Precision to Bigint with PostgreSQL. How can I do that? I have tried with to_bigint(myvalue) but that function didn't exist.
3
votes
2answers
1k 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 ...
2
votes
2answers
58 views

Adding standard set of constraints (rules) to PostGIS `raster` type column

Following on from my related prior question, let me elaborate this topic a bit. raster2pgsql is a raster loader executable that loads GDAL supported raster formats in PostGIS. It has a -C flag ...
2
votes
1answer
44 views

Good layout of 3d point data for spatial queries in Postgres?

Like shown in another question, I deal with a lot (>10,000,000) entries of points in a 3D space. These points are defined like this: CREATE TYPE float3d AS ( x real, y real, z real); If I am ...
2
votes
1answer
15 views

Is 'internallength' always useful in custom type definition in Postgres?

In our database we use a custom type to store 3D locations: CREATE TYPE float3d AS ( x real, y real, z real); In many examples I see INTERNALLENGTH used as a parameter with the definition of ...
2
votes
1answer
213 views

How to pass a parameter into a function

At the moment I have a view created, see it here in the answer. How can I create a function on that cross tab, so I can pass a date, and get data for the specific date? Also is it a good practice to ...
2
votes
1answer
123 views

Optimal hash technique to index large text

Erwin Brandstetter thankfully saved me from myself when I tried to create unique indexes on textual columns with large lengths. The upper limit for the insertion rate is tens of billions of rows per ...
2
votes
1answer
82 views

Character varying index overhead & length limit

I have a unique constraint on a character varying column that will mostly have lengths of approximately 600 but could get to 10 million. I have read about B-Trees, but I can't determine how much disk ...
2
votes
3answers
493 views

Change column type from varchar to text in all tables at once

I am using Postgres. I would like to change column type in all tables where column name is "description" from varchar(255) to text. If anyone knows that I would be very glad for your help.
2
votes
2answers
160 views

How slow is slow in postgres?

I'm working with postgres for the first time. I have a lot of experience with small / medium size data analysis (i.e. things that fit in ram and can be analyzed in R, Stata, Matlab, etc.), but am now ...
2
votes
2answers
188 views

UPDATE table with another table data

I want to update the table car_check field fencing.(total 40 rows).I also use postgis function. I think it's a little difficult.Any suggestions? The code is the first carid example. UPDATE car_check ...
2
votes
1answer
104 views

Is there any way to save the execution plan in a file in PostgreSQL?

By saving a plan in a file, I don't mean to view it, but force the optimizer to use the saved plan to execute some query. For example, if the optimizer chooses to do a hash join for a two-table ...
2
votes
2answers
1k views

How do I determine if a column is defined as a serial data type instead of an integer based off the catalog?

So I'm currently creating some SQL to read through the postgres (9.1) catalogs to build table definitions. However, I am encountering a problem with SERIAL/BIGSERIAL data types. Example: CREATE ...
2
votes
2answers
180 views

PostgreSQL and default Schemas

Whenever I create a brand new database in PostgreSQL Maestro it creates the following list of default schemas: Now from my understanding Schemas are like folders for organization, etc. So the ...
2
votes
1answer
504 views

PostgreSQL CREATE EXTENSION file not found error on Mac OS

On PostgreSQL 9.2.3 when trying this: CREATE EXTENSION btree_gist; I get this error: ERROR: could not open extension control file "/opt/local/share/postgresql92/extension/btree_gist.control": ...
2
votes
1answer
3k views

Declare variable of table type in PL/pgSQL

I am wondering if there is a way to declare a variable of type table in PL/pgSQL to hold query results? For instance how can I express something like: q1 = select * from foo; q2 = select * from bar; ...
2
votes
3answers
673 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 ...
2
votes
2answers
932 views

Select rows with repeat data within certain timeframe

As a follow-up question to my previous question on difficult row categorisation, I have another problem which I'm sure will be easily solvable. After this I plan on reading a good book or two on ...
2
votes
2answers
4k views

Most efficient way to add a serial column to a huge table

What's the fastest way to add a BIGSERIAL column to a huge table (~3 Bil. rows, ~ 174Gb)? EDIT: I want the column to be incremented values for existing rows (NOT NULL). I didn't set a fillfactor ...
2
votes
3answers
1k views

Replicating only significant records to specific database

I have a remote database which holds data for various databases in various locations. I want to do database replication, but only data specific to a certain database should be replicated to it. I can ...
2
votes
1answer
324 views

How do I resolve Postgresql error, “could not determine which collation to use for string comparison”?

When ever I run this SQL script I get: ERROR: could not determine which collation to use for string comparison This is what is on line 34: CREATE TEMPORARY TABLE weight_options AS SELECT ...
2
votes
1answer
553 views

Dropping indexes doesn't seem to release space to the OS. Can it?

I'm running PostgreSQL 9.1. I have noticed really alarmingly bad indexes are taking up a lot of space on my server, e.g: evlampts=# SELECT pg_size_pretty(pg_relation_size('mcdata_2011_07')) AS ...
1
vote
2answers
79 views

Creating a unique constraint on a PostGIS 'raster' type column

I am using the following command to add constraints to one of the raster image in PostGIS-2.1.3 (PostgreSQL-9.1.14). ALTER TABLE schema1.table1 ADD CONSTRAINT enforce_scalex_rast unique (rast); But ...
1
vote
2answers
65 views

Why can a new user select from any table?

When I create a user in Postgres, create user test with password 'test'; The user ends up being able to connect to every database in the instance. The user can also select from any table: # psql ...
1
vote
0answers
40 views

Pgpooladmin pcp commands does not work [closed]

After first installation of pgpoolAdmin I got an error e1002 with message "pcp_node_count command error occurred" Does anybody know why is this happen and how to fix this? Little update: just ...
1
vote
1answer
51 views

Problem with pgpoolAdmin installation

I got a problem with permissions during installation of pgpoolAdmin(newest version). The problem is when I get to window with main config that should be all okay to move to next installtion step. The ...
1
vote
0answers
104 views

PostgreSQL continuous archiving - use snapshot for base backup on AWS?

I'm new to AWS and PostgreSQL admin and have been poring over the docs trying to come up with a good backup strategy for a fairly simple setup. I have a single Amazon Web Services EC2 instance that ...
1
vote
2answers
40 views

Can I find errors without using testing data for all the branches of each function?

In PostgreSQL, syntax errors (except for trivial syntax errors) are reported while running the code in question; unlike Oracle, PostgreSQL can't find errors without running the part of the code. This ...
1
vote
2answers
58 views

How can I get PostgreSQL to not advance sequences when COPY fails?

I'm importing CSV files into a relatively simple PostgreSQL database. (The CSVs are sometimes created manually from information in a book, sometimes created from spreadsheets with a little massaging ...
1
vote
1answer
100 views

Decrease WAL file size for backup

I'm setting up a backup strategy based on WAL files archiving and transmission via rsync. As DB activity will propably be very low (less than 100 inserts/updates/deletes per day), at least in the ...
1
vote
2answers
140 views

Dynamic UPDATE fails due to unwanted parenthesis around string in plpgsql

Using PostgreSQL 9.3.4 on Mac OSX 10.9.2 with Postgres.app. I want to apply a function to all columns in a table, specifically I want to trim white space. So far I've got this in a file test.sql: ...