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Is there a means to set the owner of all objects in a PostgreSQL database at the same time?

http://stackoverflow.com/questions/1348126/modify-owner-on-all-tables-simultaneously-in-postgresql describes some nifty ways to change table and other objects to a specific user, and it works ...
10
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1answer
2k views

PostgreSQL exit status when running a file

When running PostgreSQL with a single SQL command error codes are returned as expected: % psql -c "SELECT * FROM AWDASDASDASDAS" my_db ERROR: relation "awdasdasdasdas" does not exist LINE 1: SELECT *...
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2answers
11k 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 ...
10
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1answer
9k views

PostgreSQL Database Data File Integrity Check

When running a PostgreSQL database system how do I know my database as a whole has 100% integrity? Basically how do I know if my data files and pages are all 100% good with no corruption? In the ...
10
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1answer
17k views

PostgreSQL: permission denied for relation

I'm a bit confused about setting permissions in PostgreSQL. I have these roles: List of roles Role name | Attributes | Member of ---...
10
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1answer
189 views

Why is query thousands of times slower with DESC?

I have a PostgreSQL database (AWS RDS) and ran the following queries in psql: livenet=> EXPLAIN ANALYZE SELECT * FROM outputs ORDER BY height LIMIT 10; Limit (cost=0.57..36.82 rows=10 width=...
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votes
1answer
785 views

Disable explicit commits in JDBC, detect them in SQL, or put the database in a readonly state

Background: I'm working on http://sqlfiddle.com (my site), and am trying to prevent one avenue of abuse possible there. I'm hoping that by asking about a problem I'm currently addressing, I don't ...
10
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1answer
2k views

Avoiding “Row by row” fetch method when dealing with source LOB columns

I have a legacy PostgreSQL database source (ODBC) that I'm attempting to migrate to new SQL Server schema using SSIS. I'm getting a warning saying: 'Row by Row' fetch method is enforced because ...
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5answers
2k views

Are there any professional fulltime PostgreSQL DBA's?

For my job I work on a JavaEE application with PostgreSQL as the database. Although we have a sysadmin for our productions servers, who also manages our database servers, we have no full-time DBA ...
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1answer
23k views

Performance difference between MySQL and PostgreSQL for the same schema/queries [closed]

I'm a newbie DBA, and I have experience in Microsoft SQL Server but I want to jump to FLOSS. I'm starting a company, and we develop an app (PHP) with a Postgres backend, and we did some tests ...
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2answers
2k views

Custom unique column constraint, only enforced if one column has a specific value

Is it possible to have a custom unique column constraint as follows? Suppose I have two cols, subset and type, both strings (though the data types probably doesn't matter). If type is "true", then ...
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2answers
4k 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?
9
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2answers
5k 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 ...
9
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2answers
6k views

PostgreSQL maximize performance SSD

I will have a huge PostgreSQL 9.3 database with many tables with more than 100M entries per table. This database will be basically be read-only (once I fill all the necessary tables and build the ...
9
votes
1answer
19k views

Postgres function assign query results to multiple variables

I need to assign values to 2 variable as below in Postgres function. a := select col1 from tbl where ... b := select col2 from tbl where ... How can I assign 2 values to 2 variables in one line ...
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3answers
440 views

How to avoid a cyclic dependency (circular reference) between 3 tables?

I have 3 tables: People Post Likes When I design the ER model it has a cyclic dependency: 1:N People --------< Post 1:N Post ----------< Likes 1:N People --...
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3answers
15k views

save/export PGAdmin server list configuration settings

I have a ton of configured connections listed in the Server Groups, is there a way I can save this? not just save the passwords but the Server Group Settings
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4answers
4k views

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 ...
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1answer
7k 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 "...
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2answers
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Is there a simple way in PL/pgSQL to check if a query returned no result?

I'm currently experimenting a bit with PL/pgSQL and want to know if there is a more elegant way to do something like this: select c.data into data from doc c where c.doc_id = id and c.group_cur > ...
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2answers
41k views

Forgotten PostgreSQL Windows password

This morning I’ve been trying to connect the PostgreSQL database on my Windows 7 Professional desktop. The default value is ‘postgres’, but sure enough I forgot what password I used when I originally ...
9
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1answer
8k 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 dropdb....
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2answers
1k views

How should I index a UUID in Postgres?

I'm new to PostgreSQL and somewhat new to databases in general. Is there an established way of how we should index UUID values in Postgres? I'm split between using hashing and using a trie, unless ...
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2answers
9k views

Is REINDEX dangerous?

I've been trying to COUNT(*) a table with 150,000 rows that has a Primary key. It tool about 5 minutes, so I figured out this is an indexing problem. Citing the PostgreSQL manual: REINDEX is ...
9
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1answer
466 views

What is the overhead for varchar(n)?

I wanted to ask for the meaning of this fragment from Postgres doc regarding varchar(n) type: The storage requirement for a short string (up to 126 bytes) is 1 byte plus the actual string, which ...
9
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1answer
5k views

Fast general method to calculate percentiles

I want to find n>1 percentiles of an unsorted column in PostgreSQL. For example the 20th, 40th, 60th, 80th and 100th percentile. An obvious solution is to count and sort the column and then do a ...
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1answer
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What is the difference between PostgreSQL 9.0 Replication and Slony-I?

Is there still any use for Slony-I, and if so, what is it? For clarification, from 9.0 Postgresql supports built in streaming replication.
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2answers
40k views

psql: could not connect to server: No such file or directory

The error in its entirety reads: psql: could not connect to server: No such file or directory. Is the server running locally and accepting connections on Unix domain socket "/tmp/.s.PGSQL.5432"...
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1answer
9k views

Most efficient way of bulk deleting rows from postgres

I'm wondering what the most efficient way would be to delete large numbers of rows from PostgreSQL, this process would be part of a recurring task every day to bulk import data (a delta of insertions +...
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1answer
2k views

EC2 - How to correctly back up PostgreSQL data?

Here is the setup: 1 small Amazon Linux (EBS-backed) EC2 instance with 3 additional volumes. This is both a web server and database server. One volume for code, one for the PostgreSQL (8.4) data ...
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1answer
52k views

How do I reset the postgres password for PostgreSQL on Windows?

I have installed PostgreSQL on my Windows machine for development. Now I haven't used it for a while, and have forgotten the password for user postgres (default admin user in PostgreSQL). How can I ...
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1answer
514 views

Naming conflict between function parameter and result of JOIN with USING clause

Given this setup in current Postgres 9.4 (from this related question): CREATE TABLE foo (ts, foo) AS VALUES (1, 'A') -- int, text , (7, 'B'); CREATE TABLE bar (ts, bar) AS VALUES (3, 'C') ...
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1answer
841 views

Why is a new user able to create tables in PostgreSQL?

I followed two tutorials to create a DB with: a fully privileged user link a read-only user link I then got a tip from CJ Estel's tutorial stating that "you may have inherited the ability to ...
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4answers
4k views

Determine when a PostgreSQL database was last changed

I'm looking at altering how backups are done and am wondering if there is a way to determine which databases in a postgreql cluster have not been recently changed? Instead of using pg_dumpall, I'd ...
9
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1answer
3k 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 ...
9
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1answer
3k views

restoring Postgres database: pg_restore -vs- just using psql

I am dumping my Postgres database using pg_dump (in plain-text format) and then restore it simply by using psql (with the -f option). Which begs the question: am I missing anything by not using ...
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2answers
14k views

Disable all constraints and table checks while restoring a dump

I've obtained a dump of my PostgreSQL database with: pg_dump -U user-name -d db-name -f dumpfile which I then proceed to restore in another database with: psql X -U postgres -d db-name-b -f ...
9
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1answer
454 views

How do I 'hint' the cardinality of a recursive CTE?

I'm using the following recursive CTE as a minimal example, but in general, the optimizer has to use default 'guessed' cardinalities for recursive CTEs: with recursive w(n) as ( select 1 union all ...
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1answer
2k views

Best practice for storing record metadata

What is the best practice for storing metadata of individual records in a database? I need to store common meta data such as creation time and time of last update for many tables in my database. I ...
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2answers
4k views

View Postgresql Memory Usage

I'm running Postgresql on a Ubuntu server and need to be able to monitor its memory usage. Currently I have scripts running in a one-minute cron job that monitor/log various statistics and need to ...
9
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3answers
21k 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 ...
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2answers
11k views

How to turn off header only in psql (postgresql)

I'm using PostgreSQL 9.1.X I am trying to build psql script to print results without a header but including a footer. http://www.postgresql.org/docs/9.1/static/app-psql.html From the document ...
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4answers
8k views

No NULLs, yet invalid byte sequence for encoding “UTF8”: 0x00

I've spent the last 8 hours trying to import the output of 'mysqldump --compatible=postgresql' into PostgreSQL 8.4.9, and I've read at least 20 different threads here and elesewhere already about this ...
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1answer
101 views

How can I see a query after rules have been applied?

From docs - 37.3.1.1. "A First Rule Step by Step" CREATE TABLE shoelace_log ( sl_name text, -- shoelace changed sl_avail integer, -- new available value log_who ...
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1answer
164 views

Huge mismatch between reported index size and number of buffers in execution plan

The issue We have a query like SELECT COUNT(1) FROM article JOIN reservation ON a_id = r_article_id WHERE r_last_modified < now() - '8 weeks'::interval AND r_group_id = 1 AND ...
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2answers
278 views

Find rows where integer sequence contains a given subsequence

Problem Note: I refer to the mathematical sequences, not the sequences mechanism of PostgreSQL. I have a table representing sequences of integers. The definition is: CREATE TABLE sequences ( id ...
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1answer
450 views

In Postgres, how to get a list of current defined savepoint?

I'm using postgres SAVEPOINT which create a new savepoint within the current transaction, and would like to display the list of currently defined savepoint in a connection. To be more precise: I'd ...
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2answers
4k views

Can PostgreSQL create a case sensitive database?

I'm porting some code from some version of Sybase to PostgreSQL. This is a C application that uses the Sybase client library. My approach is to write a translation layer that translates calls to ...
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1answer
68 views

When are privileges listed in \l and when not?

When are access privileges listed by \l, and when are they not? The access privileges listed by \l can change after a grant and revoke: $ createuser -EP my_readonly $ psql development development=# \...
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1answer
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Fast hamming distance queries in postgres

I have a large database (16M rows) containing perceptual hashes of images. I'd like to be able to search for rows by hamming distance in a reasonable timeframe. Currently, as far as I properly ...