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7
votes
1answer
264 views

How should we handle rows which won't be queried once they are old in PostgreSQL?

We have a table in a PostgreSQL database which is growing on the order of millions of rows per day. Each row consists of: ID Foreign user ID Date and time Other data The date and time aren't ...
6
votes
1answer
426 views

Compacting a sequence in PostgreSQL

I have a id serial PRIMARY KEY column in a PostgreSQL table. Many ids are missing because I have deleted the corresponding row. Now I want to "compact" the table by restarting the sequence and ...
6
votes
1answer
1k views

PostgreSQL “freeze”/“unfreeze” command equivalents

In Derby (an embedded database written in Java which is mostly used for testing or prototyping) there are "freeze" and "unfreeze" commands which can be used during an online backup. "Freeze" simply ...
5
votes
3answers
3k views

Maximum number of databases for single instance of PostgreSQL 9

Developing a multicustomer application we plan to use a different database for each customer. But it could be more than 1000 customers (applications). Will PostgreSQL handle it without any problems? ...
4
votes
1answer
80 views

DISTINCT ON vs ROW_NUMBER() for getting a row with a maximum value of a group

I have the following table in PostgreSQL 9.4: CREATE TABLE dpa( id serial NOT NULL, currency_id integer, amount numeric(14,3), date timestamp without time zone, plat_id integer, pl_id ...
4
votes
2answers
375 views

What causes large INSERT to slow down and disk usage to explode?

I have a table of about 3.1 million rows with the following definition and indexes: CREATE TABLE digiroad_liikenne_elementti ( ogc_fid serial NOT NULL, wkb_geometry geometry(Geometry,4258), ...
4
votes
1answer
9k 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; ...
4
votes
2answers
4k views

How to conditionally stop a psql script (based on a variable value)?

Let's consider the following example (from the start of a psql script): \c :db_to_run_on TRUNCATE the_most_important_table; -- tried to avoid similarities to anything that exists out there Now if ...
4
votes
1answer
1k views

Creating UUID extension as the non super privileged user

I need to load the uuid extension on my database, which is being created in runtime. The user that created the db is not superuser, she only has the "CREATEDB" permissions. Is there a way to do this? ...
3
votes
1answer
71 views

Specifying a username while running initdb causes error in log on start of PostgreSQL process

I have been forced to use a different default username for PostgreSQL. Before you ask: no, this is not something I can avoid. It's dumb, I know. Let's move on: In order to do this in an existing Cent ...
3
votes
3answers
142 views

PostgreSQL trigger function that selects from %current% table

I have multiple tables that have the same column names, they only vary in their column values, like: tbl_log_a tbl_log_b tbl_log_c ... 26 tables from a to z. Each table has a trigger that calls a ...
3
votes
1answer
770 views

SELECT in trigger function in two tables

My table and trigger in PostgreSQL 9.4.3 on x86_64-unknown-linux-gnu, compiled by gcc (Debian 4.9.2-10) 4.9.2, 64-bit: CREATE TABLE measurements ( measurement_id SERIAL PRIMARY KEY NOT NULL, ...
3
votes
1answer
136 views

Subquery magic in PostgreSQL

I have a query: update product_product set (write_date, default_code) = (LOCALTIMESTAMP, 'update') where product_tmpl_id in ( select distinct product_tmpl_id from product_template ...
3
votes
2answers
502 views

Slow fulltext search due to wildly innacurate row estimates

Fulltext queries against this database (storing RT tickets) seem to be taking a very long time to execute. The attachments table (containing the fulltext data) is about 15GB. The database schema is ...
3
votes
1answer
43 views

Why does the behavior of array syntax differ from '(?,?)' syntax when updating a point field and that field is NULL?

I'm using PostgreSQL 9.3.5. Suppose I have the following table: CREATE TEMPORARY TABLE point_test ("name" varchar(255), "pt" point); I then insert a row, leaving pt NULL: INSERT INTO point_test ...
3
votes
1answer
95 views

How do I automatically set meta commands when starting psql?

When I start a psql session, I would like certain meta commands to already be set. For instance: \x auto \set ON_ERROR_STOP on I was hoping to find an rc or config file but couldn't. The command ...
3
votes
3answers
13k views

Bulk update of all columns

I am wondering if PostgreSQL has an update query somewhat like their insert values syntax. I have an updated set of data in this form currently: INSERT INTO ...
3
votes
2answers
4k views

Postgres 9.2 select multiple specific rows in one query

I have a table with three columns, Id Serial. Value real. timein Timestamp. I want to select the values based on a range of days ie. from two days ago until now. The table may contain one or two ...
3
votes
1answer
7k views

Select first row (grouping) + add aggregate function

First have a look at this question on StackOverflow. I'm looking to accomplish the same task, except I also need to add an aggregate function (PostGIS's ST_Union) to my query. How can I combine the ...
3
votes
2answers
4k views

Get all partition names for a table

I want to list all the partitions created by dynamic triggers in PostgreSQL 9.1. I was able to generate a count of partitions using this related answer by Frank Heikens. I have a table foo with an ...
3
votes
1answer
393 views

Postgres Backup queries on AWS after reading Postgres docs

I am reading backup section of postgresql docs before heading over to create backup strategy on my EC2 instance. So there are 2 ways to do it. Create a dump using pg_dump. File level backup with ...
3
votes
2answers
2k views

Running a CTE query in a loop using PL/pgSQL

I'm trying to execute query that is repeatedly called in a loop using plpgsql -the loop iterates over another table (named coordinates) that contains top left and bottom right latitude/longitude ...
3
votes
4answers
3k views

migrating tables from Postgres to SQL Server 2008

(I fear what I wish to accomplish shall not be easy, but a lot of my googling around about it yielded rather dated results, so here it goes...) I have a Postgres 8.4.x database with over 100 tables. ...
2
votes
1answer
106 views

How to estimate reindexing time?

How do you estimate the total time reindexing an entire table will take in PostgreSQL? I have a large PostgreSQL database, the primary table of which has 15 million rows with 100 columns and 200 ...
2
votes
4answers
178 views

ERROR: check constraint is violated by some row

I've got the following error: ERROR: check constraint "cc_at_least_one_mapping_needed" is violated by some row Query: ALTER TABLE integrations.tax_aggregates DROP COLUMN IF EXISTS myob_id, ADD ...
2
votes
1answer
76 views

PostgreSQL not using index during count(*)

I have a COUNT(*) query in PostgreSQL that runs often, and looks like: SELECT COUNT(*) FROM customer WHERE source_id IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16); This query ...
2
votes
1answer
90 views

Foreign key for array column

I have a table: CREATE TABLE methods ( method_id serial PRIMARY KEY, method_name varchar(100) ); I want now to create a table with the following columns: CREATE TABLE ...
2
votes
1answer
47 views

How to make unique check without creating heavy index in postgres

I need to implement unique check for INSERT and UPDATE operations, but I would prefer to avoid creating heavy unique index (which is approx 12Gb now) on my table. Now I have unique partial index and ...
2
votes
1answer
425 views

Can't alter default privileges

I followed the steps below. I installed PostgreSQL. I logged in as postgres via (sudo -i -u postgres) I created new user new_user via shell script createuser --interactive I granted that user ...
2
votes
2answers
2k views

PostgreSQL: how do I list all triggers that use a specific field?

for example i have a student table with (studentid) i want to get a list of triggers that use this field... for example if in table X there is a trigger that uses studentid i want it to be shown in ...
2
votes
1answer
3k views

PostgreSQL update and delete property from JSONB column

From this article, I tried to update or delete property of a JSONB column: CREATE TABLE xxx (id BIGSERIAL, data JSONB); INSERT INTO xxx(data) VALUES( '{"a":1,"b":2}' ); SELECT * FROM data; id | ...
2
votes
2answers
256 views

Index for numeric field is not used

I have PG server (9.0.4) installed on Debian x86. In one of my tables I use numeric(6,1): CREATE TABLE mytable(name text, numfield numeric(6,1)) Also index created for this field: CREATE INDEX ...
2
votes
1answer
107 views

Inserting into related tables

I have a database setup with the following schema: CREATE TABLE siteInfo ( siteID SERIAL NOT NULL, siteName TEXT NOT NULL, siteHost TEXT ...
2
votes
1answer
504 views

Proxy authentication for PostgeSQL

The following seems likely to be a fairly common situation, but I haven't seen any solutions. I have a PostgreSQL database containing views that are specific to the $user, in order to restrict data ...
2
votes
1answer
467 views

Can't list users - “select * from user” returns only one row with one column

I have a heroku postgres add-on database with a user table. However, when I attempt to select * from user, all I get is: current_user ---------------- rtsjlhdfptlaqd (1 row) The table name is ...
2
votes
1answer
4k 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 based on that crosstab() query , so I can pass a date, and get data for the specific date? Also is it good ...
2
votes
2answers
998 views

How to do WHERE x IN (val1, val2,…) in plpgsql

I would like to update a selection of rows in a table; this works... UPDATE t1 SET col1 = 'newvalue' WHERE col0 in (2, 4, 5); But how can I do the same in a plpgsql function? The following gives a ...
2
votes
1answer
510 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 other user's profiles, via: ...
1
vote
1answer
31 views

Insert multiples rows/columns - PostgreSQL 9.2

I've got a table that has several columns, But I need to insert data into two columns of that table. I need to add data into those columns, from a select statement. Would it be something like: ...
1
vote
1answer
82 views

Select ONE most recent post for each author

I'm sure its a simple question and I suppose it was asked many times, but I just can't figure it out from other answers, sorry. I use recent versions of PostgreSQL and MySQL. I have 2 tables: CREATE ...
1
vote
1answer
45 views

How to view tuples changed in a PostgreSQL transaction?

BEGIN; INSERT INTO foo_table(foo_column) VALUES('a'),('b'),('c'); -- SELECT * FROM pg_stat_activity WHERE ... -- shows records with a flag if they have been added/deleted/updated END; Is ...
1
vote
3answers
266 views

Remove duplicate values from query result

I am using Postgres 9.3.9. I have 2 tables : f_agent : CREATE TABLE f_agent ( f_agent__id bigserial NOT NULL, f_agent__total_users integer NOT NULL, f_agent__dim_time_id integer NOT NULL, ...
1
vote
2answers
867 views

Can I select data inserted in the same uncommited transaction?

Maybe this is a dumb beginner question, but I cannot find an answer anywhere. Everywhere I read about the Transaction Isolation which solves the visibility of data within the concurrent transactions. ...
1
vote
2answers
215 views

Reset the sequence of a serial PK with dynamic SQL

How can I dynamically reference a sequence name (as below) using a combination of strings and DECLARE variables? Is the code below proper or is there another method of doing this? My goal is to do ...
1
vote
4answers
88 views

PostgreSQL execute a default query when no row are returned

I need to calculate the average score of a list of userId. I have a table user_place_score: (user_id, place_id, score) Sometimes I do not have the score (no row for (user_id,place_id) in the ...
1
vote
2answers
2k views

Is there a faster way to get UNION ALL behavior in Postgres?

I have a table (t0), in my Postgres DB, with data that looks something like this: t1_id t2_id 1 1 2 1 2 1 4 null 4 null 5 null And I have a query to return my ...
1
vote
0answers
175 views

Multischema view for postgres , querying multiple databases

Im managing SaaS app where each customer has a separate database (Postgres 9.3) . I need to figure out the best way to aggregate and query this data ( READ-only ). I know postgres has problems with ...
1
vote
2answers
3k views

Unnest multiple arrays into rows

I have been shown a great way to bulkinsert with this example: WITH p AS ( INSERT INTO parent_table (column_1) SELECT $1 RETURNING id) INSERT INTO child_table (parent_table_id, ...
1
vote
2answers
502 views

Restoring the superuser account on the postgres server

I have a complete curious situation with a postgres dbms. I have installed the database and due to a misconfiguration of my installation scripts I made the superuser role to be a regular user. Now I ...
1
vote
0answers
303 views

Reset postgresql [closed]

I have trouble: I tried to restore PG backup from CentOS on my Ubuntu computer. But had a trouble: after placing backuped Centos /var/lib/pgsql/9.1/data/ to my /var/lib/postgresql/9.1/main at Ubuntu, ...