PostgreSQL is a powerful, open source object-relational database system. It has more than 15 years of active development and a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness. It runs on all major operating systems, including Linux, UNIX ...
1
vote
1answer
25 views
PostgreSQL vs MySQL benchmarks when a 2nd level cache is included
Has anyone been able to find any benchmarks comparing PostgreSQL and MySQL performance when they are used by a system through Hibernate (or another comparable ORM) and the 2nd level cache (backed by ...
8
votes
1answer
133 views
Why does NOT IN with a set containing NULL always return FALSE/NULL?
I had a query (for Postgres and Informix) with a NOT IN clause containing a subquery that in some cases returned NULL values, causing that clause (and the entire query) to fail to return anything.
...
1
vote
0answers
36 views
Oracle to PostgreSQL
I'm having som test databases running Oracle 10 & 11 that I plan to try to migrate to PostgreSQL.
Some googling hinted that the perl script "ora2pg" could be of use, and free of charge. However, ...
0
votes
0answers
38 views
postgreSQL schemas, select same table from all schemas
My app is used by about 80k users every month. I want to create separate postgreSQL schemas for each user (a-la SaaS, for protection).
My app allows users to search each other profiles, simple
...
1
vote
0answers
31 views
PostgreSQL Dump: One row discarded
I created a database "my_db" and made it spatial:
psql -U my_username -d my_db -f /usr/share/postgresql/8.4/contrib/postgis.sql
psql -U my_username -d my_db -f ...
3
votes
4answers
74 views
Improve sort performance in PostgreSQL?
I've got a simple blog database in postgres-8.4 which has two tables, articles and comments. I have a query (generated by Django) that wants to get the latest article of type 'NEWS' and also find the ...
2
votes
2answers
67 views
How to convert PostgreSQL to MySQL
How can I convert database from PostgreSQL to MySQL?
I have the postgresql dump file already and I try to use pg2mysql script, it converted but when uploading the file it produces this error:
ERROR ...
1
vote
2answers
63 views
Improving performance of nasty nested-view joins
I have a moderate-sized database spread out over a few tables, the rough architecture is:
Input Data (Data ID, Session ID and a few fields of statistical importance)
Input File (Data ID and a blob)
...
10
votes
3answers
311 views
Is the CPU performance relevant for a database server?
This is a purely theoretical question. Let's say I have an application deployed on multiple servers.
A load balancer,
Multiple/scalable applications servers
A (single) database server (for the ...
4
votes
1answer
48 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 ...
0
votes
0answers
9 views
is it possible to sync Pervasive SQL database to a Postgresql database?
I was wondering if its possible to sync a pervasive sql database to a postgresql database. If i set this up i would need the ability to sync both ways either on command or via schedule. Anyone know if ...
2
votes
1answer
83 views
I need to run VACUUM FULL with no available disk space
I have one table that is taking up close to 90% of hd space on our server. I have decided to drop a few columns to free up space. But I need to return the space to the OS. The problem, though, is ...
0
votes
1answer
19 views
How to export a table on postgresql command line
Anyone can do tell me how to do that?
(I know maybe is a dumb question but I'm trying to learn how to use command line of postgresql)
~$ psql mybase
psql (9.1.3)
Type "help" for help.
and then
...
-1
votes
1answer
81 views
Important distinctions between DBMSs [closed]
DBA is a career I'm strongly considering after school, but my limited experience mostly involves some PL/SQL Oracle web programming, some basic PHP/MySQL web pages, and some queries in SQL Server. ...
0
votes
0answers
67 views
Rotate a table in PostgreSQL
Problem description
I need to rotate (with DROP and CREATE) a table which is heavily used by other clients.
At present, I have a program which replaces (DROP + CREATE) this table.
Sometimes, just ...
