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Questions tagged [postgresql]

All versions of PostgreSQL. Add an additional version-specific tag like [postgresql-13] if that context is relevant.

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1 answer
230 views

How to improve restoring the PostgreSQL database?

I'd like to restore the PostgreSQL database from a dump. The below command works fine for me: CALL "%PGBIN%\pg_restore" -c -d NetCatalog %DUMPFILE% How can I add a few lines to my .bat file to ...
2 votes
1 answer
2k views

Postgres - how to randomize two columns in a table

I have a table of User data which I would like to disguise/anonymize. Two of the columns have location data (e.g. lat and long, both BigDecimals). I have anonymized all the names and other ...
1 vote
1 answer
411 views

Show all variations of 2 characters in postgres

How would I do this in postgres : Lets say I have an x and a y and I want to show all possible combinations : xx yy xy yx How can I make postgres do this for me ?
1 vote
1 answer
8k views

Postgres Administration roles

I need to work with a remote postgresql server. My application needs to perform the following actions: to be able to create/drop database (I only need to work with 1 specific database) to be able to ...
4 votes
1 answer
2k views

How can I escape XML field in XML-output query?

I have following request: SELECT XMLAGG(data) FROM (SELECT XMLELEMENT(name item, XMLFOREST( title, body as description, date_created as date, 'http://example.com/news'||id as link )) AS ...
2 votes
1 answer
3k views

Postgres Index scan forward vs backward = speed difference of 357X slower

PostgreSQL 9.1.2 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-51), 64-bit Dedicated DB server 4GB ram Shared_Buffers = 1 GB Effective_cache_size = 3GB Work_mem = ...
9 votes
2 answers
2k views

Pros and Cons of Checking if value exist for unique column or let db raise unique error on inserting

While writing a query other day a thought came to me and have stuck in my mind. What is preferable, first checking if a value for a unique column exists and then inserting or insert and let db raise ...
11 votes
2 answers
16k 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 ...
4 votes
1 answer
61 views

Want to add a "variable" to a table

I'm using PostgreSQL 8.4 and I have a table that is cleared out and refilled with new data every so often. I want to be able to store the date that the table was last filled, but I'm not sure where to ...
3 votes
2 answers
2k views

How does pgAdmin III build CREATE statements?

In PostgreSQL, there is no SHOW CREATE statement, known for example from MySQL. But when you use the pgAdmin III client program and go to object details, you see the corresponding CREATE statement. ...
0 votes
1 answer
612 views

Which file is PostgreSQL log file 0?

In my PostgreSQL logs, I find this message: LOG: invalid magic number 0000 in log file 0, segment 1, offset 16121856 Which file is log file 0? Here is my pg_xlog directory: -bash-4.1$ ll pg_xlog/ ...
1 vote
1 answer
6k views

restoring a table from sql file in postgresql through Windows Command prompt

Im trying to restore an sql file which contains the dumpf a table (with COPY commands) into a table into the database, it would be great if someone could share an example, as the pg_restore doesn't ...
1 vote
2 answers
11k views

Running postgresql in Mac Terminal

I have a production SQL dump file that I want to restore to my local psql db for debugging reasons. I can't access psql via the terminal though pgAdmin3 works just fine. Here is the error I'm getting:...
2 votes
2 answers
4k views

Update column by comparing date and string values together

I have problem in updating table. I need to update table by comparing date and name with another table. I have two tables: table 1 : dim_sesid name(varchar) role ...
2 votes
1 answer
648 views

Rewriting a query

I have a database with the following structure (star schema): facttable: pros integer mena integer me integer vahet double precision slutttp timestamp without time zone Structure of each ...
17 votes
3 answers
5k views

Does PostgreSQL 9.1 Streaming Replication catch up after a lag without WAL archiving?

Context: Let's say that, while using Streaming Replication/Hot Standby on a Postgres 9.1 cluster, a standby node goes down. It stays down for an day, during which time a lot of DML occurs on the ...
11 votes
2 answers
8k 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 ...
2 votes
1 answer
671 views

Why is a duplicate record inserted when it should not be?

Why does this command insert into "deliveryLog" select * from temp_dellog where "deliveryID" < 15620652 give this output? ********** Error ********** ERROR: duplicate key value violates unique ...
6 votes
1 answer
511 views

in postgres, can one optimize a table across partitions?

in a database with many companies, segregating them using schema and search_path almost all access comes at the company level, that is, limited to a single schema. some data-warehouse and accounting ...
1 vote
1 answer
464 views

Using PL/PerlU with a non system perl lib

psql -1f check_email.pl.sql ccushing postgres SET psql:check_email.pl.sql:7: ERROR: Can't locate Email/Valid.pm in @INC (@INC contains: /usr/lib/perl5/site_perl /usr/share/perl5/site_perl /usr/lib/...
2 votes
1 answer
3k views

Postgresql 9.1 replication delay

I just set up a PostgreSQL 9.1.2 database server on debian squeeze. I configured a standby server (hot standby) on a second identical server (squeeze, PG 9.1.2). On the master I set these parameters (...
24 votes
2 answers
18k views

Trigger: move deleted rows to archive table

I have a small (~10 rows) table called restrictions in my PostgreSQL database, where values are deleted and inserted on a daily basis. I would like to have a table called restrictions_deleted, where ...
24 votes
1 answer
7k views

Is there a good way to run a trigger for each record in a postgres table?

I have a system where I can't control the design of some tables (replicated via Slony-I), and so I have a series of what we refer to as 'shadow tables', where I extract some information out of the ...
4 votes
2 answers
761 views

Plpgsql seems to be deleting and inserting instead of updating - Why?

I am using postgreSQL 7.4. I have a large table , call it table_a: key1 INT NOT NULL, key2 INT NOT NULL, data INT NOT NULL, itstamp INT NOT NULL DEFAULT (date_part('EPOCH'::text, (timeofday())::...
3 votes
1 answer
2k views

Any Idea how to migrate from PostgresSQL 8.4 to PostgresSQL 9.1.1 in opensuse12.1

I had a crashed opensuse 11.3 that's why I installed opensuse 12.1.. after I installed (via yast) and edited /etc/passwd I do this: rcpostgresql start and this shows on the /var/log/messeges ~ # ...
0 votes
0 answers
50 views

postgresql view [duplicate]

Possible Duplicate: postgresql view with max min with id I have the following table: CREATE TABLE trans ( id SERIAL PRIMARY KEY, trans_date date, trans_time time ); I want ...
3 votes
3 answers
1k views

Replication chaining with PostgreSQL

We have an unusual replication scenario and I am not sure which tool would be appropriate for that. Basically, we have a legacy non-normalized database that we want to refactor into a normalized ...
1 vote
1 answer
2k views

64 bit Postgres 9.1 Limitions on Windows 2008 R2?

When Deploying Postgres on Windows Server 2008 R2: Are there any limitations on windows that don't exist on Linux? Does the postgres scale in the same way on windows as it does on Linux? Is ...
1 vote
3 answers
370 views

PostgreSQL and query planner

I have question about query planner in PostgreSQL. I know, that this planner is taking data from pg_statistics, but... Can anyone tell me on what basis this planner is taking those informations to ...
8 votes
3 answers
16k views

PostgreSQL vs. Oracle High Availability solutions?

PostgreSQL has a matrix of different high availability options which represent many different ways of building replication into an RDBMS. Here is the PostgreSQL High Availability, Load Balancing, ...
5 votes
2 answers
3k views

VACUUM and VACUUM FULL do not return space to OS

I'm running Postgres 8.3.3. I have a postgres database on a Linux filesystem that is quite full. I've run VACUUM and VACUUM FULL, yet none of the space has been returned to the OS. When I observe ...
4 votes
1 answer
834 views

Single node parallelism with PL/Proxy?

I have seen some suggest that single node parallelism is possible, but all of the material I have found so far deals with parallelizing across nodes. I am interested in getting large static queries to ...
7 votes
1 answer
890 views

PostgreSQL partition hierarchy design for centralized logging

I am looking into setting up logging from all of my servers into a centralized postgresql database. It makes sense to be able to drop logs by date or by host, so I'd like to set it up with ...
5 votes
1 answer
2k views

Storing bitsets in PostgreSQL?

I need to calculate reach, grouped by different criterions, and would prefer to keep everything in my database. I'm looking for either a pre-built bitset implementation for PostgreSQL, or pointers on ...
11 votes
2 answers
5k views

PostgreSQL: reuse of complex intermediate result in same query

Using PostgreSQL (8.4), I'm creating a view that summarizes various results from a few tables (e.g creating columns a, b, c in the view), and then I need to combine some of these results together in ...
7 votes
2 answers
8k views

What is the purpose of PGBouncer's parameter server_reset_query?

Recently I started learning about pgbouncer, but there are some things I do not understand about the parameter server_reset_query. Question 1: What is the main purpose of server_reset_query? ...
6 votes
3 answers
6k views

Is there a need to keep refreshing the indexes from time-to-time?

This question is common for all the database products I use, viz. SQL Server, MySQL, Oracle and PostgreSQL. I have created a fresh database and the tables, at present, have no records. I have created ...
7 votes
1 answer
6k views

Does my choice of pg_dump format impact restore speed?

According to the docs for my version of Postgres (8.4.2), pg_dump can "output in script or archive file formats." The script-formatted dump (4GB) takes 1.5 hours to restore, and I'm wondering if the ...
2 votes
3 answers
518 views

New Job and Company uses PostgreSQL [closed]

I have used MySQL and SQL server all of my professional career. The company I will be working for uses PostgreSQL. Can someone who was/is in a similar situation please give me some insight on what ...
2 votes
1 answer
6k views

PostgreSQL replication: out-of-sequence timeline ID, when former master made slave

I've configured master slave replication in PostgreSQL, following this tutorial: http://wiki.postgresql.org/wiki/Binary_Replication_Tutorial#Binary_Replication_in_6_Steps It worked fine. Now I've ...
13 votes
1 answer
13k views

Type conversion with default fallback value

In PostgreSQL (8.4), I'm trying to convert a string parameter into a date within a SQL query, falling back to now() when the string is not a valid date (or empty). In "pseudo-SQL", this would be ...
2 votes
2 answers
533 views

Database Transfer from PostgreSQL to MySQL

Is there any method to tranfer the data and schema from a postgresql database to mysql?
7 votes
4 answers
18k views

Visualization of MySQL/PostgreSQL table structure as a graph/UML

Is there any program, source code or API that will take a MySQL or PostgreSQL schema and spit out a UML or some other graph visualizing of it?
5 votes
1 answer
1k views

PostgreSQL pl/perl trigger, differentiate null vs empty

I've been trying to speed up a generic auditing trigger that I had written in pl/pgsql some time back. On update, it generates a list of columns in the table being updated and inserts rows in the ...
3 votes
3 answers
621 views

Can I limit access to postgresql 8.4 databases via ODBC on the server side?

I have a bit of a tricky problem at the moment that I could really use some help to solve. I'll do my best to explain it but please feel free to ask questions :-) We have a postgresql 8.4 database ...
7 votes
2 answers
9k views

Reference a non primary key in another table in postgresql

I have a two columns should references two columns in another table. And those two columns are not primary key. I think I can't use foreign key, because it can only references primary keys.
2 votes
1 answer
641 views

How to perform asynchronous cascade slave replication of PostgreSQL database?

This is a feasibility/architectural question (I am no database administrator). Let's imagine a PostgreSQL database running online (like those from Heroku for example). One would like to maintain a ...
7 votes
2 answers
5k views

Is there any index with O(1) complexity for lookup in PostgreSQL?

Is there any index type in PostgreSQL that gives O(1) complexity for lookups? on strings?
10 votes
3 answers
3k views

Postgres, MVCC, and Locking

I have a series of SQL statements that look like the following: BEGIN; SELECT counter FROM table WHERE id=X FOR UPDATE; REALLY COMPLEX QUERY; UPDATE table SET counter=Y WHERE id=X; END; I'd like to ...
6 votes
1 answer
20k views

How can I generate scripts for all functions in pgAdmin?

I am using pgAdmin version 1.10.5, and I've checked the properties and menu options but couldn't find anything on the subject. For example, I just want to generate a script that includes the ...