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2
votes
2answers
2k views

Return several values from a PL/pgSQL procedure - to speed up the query

I have a non-forking game daemon written in Perl, which uses acync queries to write player stats into a PostgreSQL 9.3 database. But when I need to read something from database (like if a player is ...
2
votes
1answer
445 views

PgBouncer Uncertainties

I'm trying PgBouncer for the first time with a simple Python web application (Flask + psycopg2), and I have a hard time interpreting the meaning of its log messages by simple googling. I'm basically ...
1
vote
2answers
4k views

How to CREATE TABLE … LIKE without the NOT NULL Constraints?

I'm trying recreate a table's structure inside a function by using some dynamic SQL. EXECUTE 'CREATE TABLE ' || my_table_name || '_bk' || ' (like ' || _my_table_name || ')'; That will be ...
2
votes
1answer
368 views

PostgreSQL WHERE clause with two OR'ed conditions, priority to first

I'm storing user data (username, email, password hash) in PostgreSQL, and I can only enforce uniqueness on username. I'd like to let users provide either their username or their email when they login. ...
3
votes
1answer
518 views

Add NOT NULL constraint to large table without table scan

Trying to add a NOT NULL constraint to a table with 1 billion rows. I cannot afford a table lock for more than a couple of seconds. Is there a way to prevent a full table scan during the alter table ...
0
votes
0answers
126 views

ZLM 7.3, postgres database must be vacuumed within x transactions

We have a legacy ZLM 7.3 IR4 primary server running on a SUSE 10.4 server with a local postgresql (8.1.23) database. We are getting the following warning from the nightly vacuum cron script ...
0
votes
0answers
55 views

compare time difference between current time with last data timestamp

I have a data server recording data every second. i need to setup a cron job that that runs a script that can give a reply if the now() is 24 hours more than the last data recorded. So that I can ...
1
vote
1answer
3k views

Have Postgresql query planner use nested loop w/ indices over hash join

I'm having a problem with some StackOverflow-schema related data loaded into PostgreSQL 9.3.4. I have a query that is taking about 10x longer than it should, due to the fact that it is choosing to use ...
7
votes
2answers
5k views

Compare two similar Postgres databases for differences

I occasionally download publicly available data sets in the form of Postgres dBs. These datasets are updated/modified/expanded over time by the repository host. Is there a Postgres command or ...
-2
votes
1answer
1k views

postgres: how to use subquery correctly?

I have the following query CREATE TABLE test_buffslip AS SELECT ST_INTERSECTS( (SELECT ST_Buffer(geom, 0.005) FROM segments where class = 7) ,geom) FROM segments; resulting in ...
0
votes
0answers
856 views

PostgreSQL --initdb fails on pg_authid - FATAL [closed]

I have installed postgreSQL. but when I try to do initdb it leads to FATAL ERROR.. $ /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data/ The files belonging to this database system will be owned ...
2
votes
2answers
297 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
263 views

Import using pgAdmin3 produces ERROR: duplicate key value violates unique constraint

I am importing from the GUI a CSV file into a table. I have created the following table: CREATE TABLE jira_tickets.daqa_rpt_tbl ( daqa_report_id bigint NOT NULL DEFAULT ...
2
votes
1answer
2k views

Better way to restore to existing pg database

We want to restore to an existing 9.3 pg database. What we ended up doing was: 1) delete the database and recreate again, 2) use pg_restore to restore. 3) reboot the ubuntu server to allow rails ...
1
vote
0answers
550 views

Postgresql - How to Convert all Column Names to Lowercase

I have a travel survey with a series of tables (lots and lots of columns) that I exported from MS Access into a postgres database. I've search around a lot for an explanation of how to convert all the ...
21
votes
6answers
2k views

Count where two or more columns in a row are over a certain value [basketball, double double, triple double]

I play a basketball game which allows to output its statistics as a database file, so one can calculate statistics from it that are not implemented in the game. So far I've had no problem caluclating ...
2
votes
1answer
63 views

Postgresql import user from linux

I install postgresql 9.2 on a Ubuntu 12.10 machine I tried to import linux's user to postgresql but only way I can figure out is CREATE USER Jack WITH PASSWORD '1234'; and do it 10 times (if ...
1
vote
2answers
835 views

trigger_file doesn't work

I set streaming replication. Replication works just fine but it doesn't care about trigger_file. I have nothing fancy there except all what many of tutorials advices: recovery.conf: standby_mode = ...
1
vote
1answer
1k views

Recursive calls in stored procedure and temporary tables

I am trying to create a stored procedure in PostgreSQL which has recursive calls. The procedure creates a temporary table to store results. The temporary table isn't dropped after first call due to ...
2
votes
1answer
126 views

Organizing Database Objects in a Database that are not part of the systems original Database Objects?

I've been working at a place for about 2 years now with a series of heterogeneous legacy database applications, which are tied together using 3rd party Microsoft Access databases (*.mdb). Soon we ...
1
vote
1answer
353 views

Table variable not Recognized in stored procedure

The following stored procedure for a postgresql database attempts to insert into a temporary table 'result' of type result_load_status ,which is a table in database, and return this temporary table. ...
1
vote
1answer
378 views

TRUNCATE in transaction: dead lock

In a unittest we run this: BEGIN; TRUNCATE table1; TRUNCATE table2; ... UPDATE ...; ROLLBACK; Unfortunately this results in a dead lock if a cron job starts and this job operates on table1 and ...
2
votes
1answer
60 views

How can I know whether postgres is currently running synchronous or asynchronous replication?

I see from ps that: postgres: wal sender process replicator X.X.X.X(38681) streaming 0/17AF5438 But is there any way for me to know whether it is synchronous or asynchronous? I made the relevant ...
1
vote
1answer
157 views

capability and performance of tags implemented as array vs text vs full text

In terms of search capability and performance, what are the pros & cons of implementing tags as an array or text or full text field? I am seeing limitations of capability in choosing to implement ...
3
votes
1answer
110 views

Understanding postgres prompts

What is the difference between postgres=# and postgres-#? I tried googling it and looking on the official site but could not get a hit for the symbols.
1
vote
0answers
20 views

Storing generated documents that can not be updated by changes in relationships

I have a system running with PostgreSQL and Yii Framework, which generates a few medical documents that, once ready, can't be changed. For example: If my full name comes out on this document today, ...
4
votes
3answers
4k 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.
0
votes
0answers
89 views

PostgreSQL Failover strategy

I'm lost when it comes to choose the failover technology for my postgresql database. The options I currently see are: PG Cluster Streaming Replication Warm Standby (log shipping?) Hot Standby Is ...
2
votes
2answers
590 views

In PostgreSQL is there a way to rank/weigh columns so as to order the results?

Let's say I am searching through three text columns. I don't just want results that match a given word or phrase, but I also want to weigh them (column A > column B > column C) - thereby ...
2
votes
2answers
5k views

Moving a Postgres database from standalone local DB to Amazon RDS

I have a working Ruby on Rails 4 app running locally on my Mac. I'm running Postgres locally. I want to move the database (and only the database, not the whole app) to Amazon RDS Postgres. What is ...
5
votes
1answer
199 views

If PostgreSQL starts after copying data, is the data ok?

I'm copying the data for a PostgreSQL database, that is, /var/lib/postgresql, from one server to another. The servers are identical except for the fact that one is 32bit and the other one is 64. I ...
3
votes
2answers
665 views

Optimize a query on two big tables

I have a very important query in my system that is taking too long to execute due to huge amount of data on tables. I'm a junior DBA and i need the best optimization I can get for this. Tables have ...
3
votes
1answer
205 views

How can I achieve clustering of rows without the exclusive lock and logging overhead of the `cluster` command?

The CLUSTER command on a big table can take a long time, and blocks both reads and writes to the table while it runs. I don't need the data in my table to be strictly sorted in index order, I just ...
0
votes
1answer
918 views

Restore postgres in command line on ubuntu failed

This question may be asked many times. We are trying to move a postgres db from windows (psql 9.3) to ubuntu runing postgres 9.3. Here is what we did: In windows, create backup for db cis with ...
5
votes
1answer
189 views

Is there a configuration setting for how many pages ANALYZE will scan?

Is there a setting that controls how many records/pages are scanned by the PostgreSQL ANALYZE command? It looks like by default it scans 30,000 pages and 30,000 records. The PostgreSQL Server ...
1
vote
0answers
288 views

pgAdmin Slony Creation Scripts

I have installed pgAdmin 1.18.1 but whenever I am trying to create a new cluster using Slony-I, it is always saying that it is missing some scripts. I have copied some .sql scripts from my Slony ...
0
votes
1answer
238 views

Easy way to replace an YAML array of IDs with strings from a joined table

I have a database full of camp data. Each camp has many campers and has many camp_weeks. In the table of campers, there is a YAML encoded array of IDs for the camper's camp weeks. The project ...
1
vote
2answers
380 views

Why does 'plpgsql' not appear in the pg_extension table?

I have two Postgres 9.1 installations. One works properly, the other does not. On the working installation: dc=# select * from pg_extension; extname | extowner | extnamespace | extrelocatable | ...
1
vote
1answer
378 views

Does postgres efficiently re-use space from deleted rows?

From the docs: In PostgreSQL, an UPDATE or DELETE of a row does not immediately remove the old version of the row [...] But eventually, an outdated or deleted row version is no longer of interest ...
1
vote
2answers
431 views

When normalizing a relational database, should multiple “type” tables be combined into one?

Before making substantial changes to the content, functionality and design of my website (I'll be refactoring everything, almost a complete rewrite), I'm setting up a new PostgreSQL database to hold ...
1
vote
1answer
322 views

Index creation before or after loading data

I have a situation where I need to create a table in Postgres and add approximately 3 million rows. Currently I am adding an index to one field after all the data is loaded, but I was wondering ...
1
vote
2answers
298 views

Thai and English in a postgresql

I have a postgresql DB with Thai and English values/strings in several tables. Currently I have the following settings | Encoding | Collate | Ctype | | UTF8 | en_US.UTF-8 | en_US.UTF-8 ...
4
votes
1answer
440 views

RANGE clause error within window function

I'm trying to use postgres' RANGE clause within a window function to dynamically set the window to the past 4 weeks not including the current date. Here is my attempt at it: SELECT ...
3
votes
1answer
996 views

Using PgBarman for PostgreSQL 9.3 backup

I'm setting up a backup strategy for a PostgreSQL 9.3 db. My job includes: take db backups every day/week/month use a Synology NAS as remote backup device I'm thinking of using Postgres ...
0
votes
1answer
307 views

Postgres database dump and restore on different database [closed]

I have two Postgres databases on the same server, which have the same schemas. The goal is to have DB1 as the production and DB2, as the database that will receive all the data that is migrated from a ...
4
votes
1answer
1k views

Could not open file “pg_clog/0000”: No such file or directory

My local PostgreSql 9.2 database won't start anymore this morning. I am on Windows 7. Yesterday, I performed a Windows Update before going to bed. I have checked the log and found: 2014-05-28 ...
2
votes
1answer
462 views

Any experience with cstore_fdw? [closed]

It looks like there is a (finally) an open source columnar and compression extension for Postgres. I wonder if anyone had any experience with it yet? I've worked with Greenplum for years, but I've ...
2
votes
1answer
633 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 ...
0
votes
1answer
2k views

pgAdmin on a fresh OS X Server installation

I know for sure postgresql is running (checked with ps ax), but when I install pgAdmin and try to make a server connection to localhost I get this error: Server doesn't listen The server doesn't ...
4
votes
1answer
2k views

How do I decompose ctid into page and row numbers?

Each row in a table has a system column ctid of type tid that represents the physical location of the row: begin; create table t(id serial); insert into t default values; insert into t default ...