1
vote
0answers
11 views

Checking for multiple identical values in a Posgresql array

I have a simple table in Postgresql: CREATE TABLE data (id integer, values integer[]); INSERT INTO data VALUES (1, '{1,2,3,4,5}'); INSERT INTO data VALUES (2, '{1,1,2,3,4,5}'); INSERT INTO data ...
1
vote
2answers
22 views

PostgreSQL - summing arrays by index

I have an array of doubles column (double precision[]) in PostgreSQL that keeps half hour values for a day. So each array holds 48 values. I need an efficient query that is summing all this array ...
1
vote
1answer
28 views

How much should I care about prepared statements for simple queries?

I wonder how much I should care about prepared statements (and therefore try to optimize my code) in case of pretty simple statements. The question originates from the fact that I recently noticed ...
0
votes
0answers
13 views

pgAgent does not run

I referred this to set up a scheduled job and did everything as it mentioned(ran the pgagent.sql as well) I need a very simple task to run periodically. In the 'Definition' tab in the steps, few ...
-1
votes
0answers
24 views

Get records that have associations in other tables [on hold]

I have multiple tables such as dataset_tb, dataset_tag_tb, user_dataset_access_tb. I need to get datasets that have a specific dataset_type value in dataset_tb, in which there exists a record in ...
1
vote
1answer
15 views

Find the number of where statements that matched in postgresQL

Right now I have a query that looks something like this SELECT id FROM products WHERE products.details->'make' = ? OR products.details->'model' = ? OR products.details->'year' = ...
0
votes
1answer
14 views

How to change the mount point for a column in postgresql table?

This is my scenario I have a table t with following columns id int link varchar(500) name varchar(20) sal text In the link column we will store the location for the pdf files(mount point) ...
0
votes
0answers
19 views

Postgres - Combine similar queries with extra where clause

I am trying to combine a number of fairly time consuming queries into one (if possible) The database contains race-track data that records the times for laps completed by drivers (or users here), the ...
0
votes
0answers
14 views

Recursive query to break time intervals into standard-sized parts

I'd like to write a reusable function which takes 3 arguments a timestamp start_time a timestamp end_time an array of intervals interval_array such that each interval (except the first) divides the ...
0
votes
1answer
16 views

The number of copies for each table stored in physical storage

I am new to Postgres and the database field. My question is that how many copies of each table are stored in physical storage device (memory, disk and so on)? I assume we need more than one copies for ...
0
votes
2answers
43 views

Calculating average with AVG for a list of numbers

This is probably a newbie question (bear with me) but how can I calculate the average for a list of numbers using SQL and the AVG function? I mean, I can add together numbers in SQL like: SELECT ...
0
votes
1answer
46 views

Use serial ID for multiple columns and return it from INSERT

I am using Npgsql and I want to be able to do an insert, and if statement that will do an update and then return a value so when ExecuteScalar is called it reads that value. This was done fine in ...
1
vote
1answer
34 views

Writing a view that caches to another table

I have a table market_trades with columns timestamp, market_id, and amount: api_production=# \d market_trades; Table "public.market_trades" Column | ...
0
votes
1answer
29 views

Postgres get rows where a field stopps growing

I have a table which has the following structure id SERIAL PRIMARY KEY, device_id INT REFERENCES(another_table), uptime TIMESTAMP Every device is pinged every N minutes. The application logic and ...
3
votes
2answers
43 views

idiom to treat empty result set as zero

This is obviously a SSCCE. I have an inventory table that holds the number of items (numOfItems) in a warehouse at any given date (inventoryDate). Both are integers to keep things simple: CREATE ...
0
votes
3answers
97 views

get row count of last select query

I am using a scheduled script which exports the (new) rows of the PostgreSQL database into a textfile. There are also several instances of this script running for several DBs: COPY (SELECT ... FROM ...
2
votes
2answers
48 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 ...
0
votes
0answers
16 views

fetch datas from PostgreSQL database [migrated]

I have created two tables in a PostgreSQL database named doctor and department. I have used dept_id as foreign key in the doctor table. Now I have listed the departments in Eclipse but when I'm ...
3
votes
1answer
214 views

Optimizing large database query (25+ million rows, using max() and GROUP BY)

I'm using Postgres 9.3.5 and I have a large table in the database, currently it has over 25 million rows and it tends to get even larger rapidly. I'm trying to select specific rows (all unit_ids with ...
2
votes
2answers
86 views

SQL order by query results in any arbitrary (but reproducible) manner

For testing purposes I need to get some data from a set of database tables in any arbitrary (but reproducible) order. The idea being that I can later compare two runs using a textual diff tool. Is ...
1
vote
1answer
21 views

Handling exceptions from inside a function

I need to add a trigger after insert or update on a table so that, where some row is updated and a certain condition is met, then some other table needs to be updated. However, that last update ...
2
votes
1answer
44 views

PostgreSQL Division In Query Not Working

So I am having a really off day or something, but for the life of me I can not figure this out. I am trying to divide tier1 by total to get a percentage of the total. I thought like this: (tier1 / ...
1
vote
0answers
79 views

Implementing a functionality for processing heavy insertion

I use PostgreSQL 9.1. The scenario is: I receive heavy insertion into Table1 (about 100 rows per sec). For each new row, I have to check the previous and next row of the source table if those are ...
1
vote
1answer
74 views

Best way to add Foreign Key to massive table?

Say I have 4 tables: arrival (~100 million rows), departure (~100 million rows), airport (~30 million rows), airplane (small). arrival and departure each have 2 ForeignKeys: one to airport, one to ...
0
votes
0answers
16 views

Need separate columns that calculates percentage [duplicate]

I have the following table: NAME ------ Alex Bob Bob Tim Alex Roger I need to produce the following: Name Count Percentage ------------------------- Alex 2 33% Bob 2 33% ...
2
votes
6answers
58 views

Need separate columns that calculate percentage

I have the following table: NAME Alex Bob Bob Tim Alex Roger I need to produce the following: Name Count Percentage Alex 2 33% Bob 2 33% Roger 1 16.6% Tim 1 ...
1
vote
1answer
41 views

Upsert statement never completes, infinite loop?

Edit: The function works, tested it by creating a small table. So the problem must be with my input, but I still can't see what the issue is - unless the function is just incredibly slow. It's not a ...
0
votes
1answer
26 views

Bulk insert in multiple tables

I have two tables on which I perform some bulk inserts: key: key_id(pk), key_name related_key: key_id(fk), related_key_id First Insert: values_data = "($$key_1$$), ($$key_2$$)" INSERT INTO key ...
0
votes
3answers
55 views

PostgreSQL equivalent of MySQL query variables?

Is there a straightforward way to adapt these types of MySQL queries to PostgreSQL: setting variables in MySQL like set @aintconst = -333 set @arealconst = -9.999 It seems not. Assigning ...
1
vote
3answers
55 views

Query to return output column names and data types of a query, table or view

Is there a PostgreSQL query or command that returns the field names and field types of a query, table or view? E.g., a solution if applied to simple SELECT query like SELECT * from person should ...
0
votes
2answers
38 views

How to implement a dynamic string into a (prepared) sql statement?

I have some spatial datasets which are available in a open source metadata catalog software GeoNetwork and in a PostGIS database. The problem is that the student who created the database used ...
2
votes
3answers
138 views

GROUP BY one column, while sorting by another in PostgreSQL

How can I GROUP BY one column, while sorting only by another. I'm trying to do the following: SELECT dbId,retreivalTime FROM FileItems WHERE sourceSite='something' GROUP BY seriesName ...
0
votes
0answers
10 views

Using range types (with GiST index)

Say I have 2 tables with a PostgreSQL range column: CREATE TABLE events ( id serial, during tsrange ); and CREATE TABLE storms ( id serial, during ...
0
votes
1answer
22 views

Row-level subquery caching?

I have a query that uses a CTE which contains millions of rows. I plan to call this query many times, and the CTE returned each time will have most of the same rows. Is it possible for me to cache the ...
1
vote
1answer
18 views

Index on integer column not helping. Help? (EXPLAIN ANALYZE output inside)

The table market_trades has an integer column market_id which takes values from 1 to 5. This seems like a pretty straightforward query to get the number of trades on each market: WITH markets AS ( ...
1
vote
1answer
40 views

Optimizing a query on a large table (EXPLAIN ANALYZE result inside)

I have a table market_trades with a timestamp column: api_production=# \d market_trades; Table "public.market_trades" Column | Type ...
2
votes
4answers
94 views

Make IN clause behave like AND clause

I've asked the same question on stackoverlow, but got no answer, so that's why I'm asking it here (I've read that simple sql questions should be asked at SO, but I have no choice). Suppose I have 3 ...
2
votes
0answers
7 views

Active record relation AND filtering [duplicate]

(Edit: since reposted to dba.stackexchange.com and answered there). Suppose I have 3 models: Post, PostCategory and Category. I'm implementing some kind of page with filters where I can filter posts ...
0
votes
0answers
10 views

Multischema view for postgres , querying multiple databases. [duplicate]

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 ...
0
votes
1answer
21 views

Need some help with this query or some ideas for change it to better model

I've a dilemma in my application and I don't get how to solve it at DB level. The idea is that a user can be subscribed to one or more services but services are show depending on user type. This can ...
3
votes
5answers
102 views

Find all values not present for other values of other column

Let's suppose I have a table with integer columns a and b (each pair (a,b) is unique) and following data: a | b ------- 1 | 2 1 | 3 1 | 4 1 | 5 2 | 1 2 | 3 2 | 4 3 | 1 3 | 3 Now I need to ...
1
vote
1answer
31 views

Joining timestamped records with the most-recent-prior records from another timestamped table

Say I have 2 tables: Table: sales timestamp timestamp without time zone amount numeric Table: prices timestamp timestamp without time zone price numeric How can I get a ...
2
votes
3answers
459 views

How do I ORDER BY typical software release versions like X.Y.Z?

Given a "SoftwareReleases" table: | id | version | | 1 | 0.9 | | 2 | 1.0 | | 3 | 0.9.1 | | 4 | 1.1 | | 5 | 0.9.9 | | 6 | 0.9.10 | How do I produce this output? | id | ...
0
votes
1answer
20 views

PostgreSQL SQL syntax - JOIN and substrings

I have a single table of hostnames and NFS exports, some but not all of which are related. Example entries: HOST VOLUME ----- ---------- host1 vol1 host1 vol2 host1 ...
1
vote
1answer
47 views

Update different columns on different clauses

I have a database table in Postgres 9.3 with the following layout: id SERIAL, col1 INT, col2 INT Whenever a new row is inserted, I will have to update ALL rows col1 and/or col2 in different cases ...
0
votes
2answers
78 views

How can I make this query more efficient?

This is the query: SELECT races.*, tmptimers.last_start_time, tmplaps.updated_at AS last_updated_at FROM races LEFT JOIN (SELECT * FROM timers WHERE timers.user_id = 1) AS tmptimers ON ...
1
vote
1answer
41 views

how to update the value of a period contained inside a bigger range

I have a tsrange like '[2010-01-01 14:00, 2010-01-01 15:00]',20 And want to update the 20 value to 15 in a range inside that, like '[2010-01-01 14:10, 2010-01-01 14:30]',15 My expected outcome ...
1
vote
1answer
74 views

PostgreSQL: schema diff/patch tool

Consider the following setting: A production DB A dev db, on which schema changes are made to enable new features When the development of a new feature is complete, I have to manually update the ...
0
votes
2answers
33 views

assign selected columns to a variable

Select sum(column_a) as a, sum(column_b) as b round(a / b) From table Group by column In the example above I am summing two column, and I would like to use those 2 results in calculating ...
1
vote
1answer
38 views

Does PostgreSQL allow multiple grantees in GRANT commands?

Looking at the PostgreSQL docs it seems that the GRANT command only grants to a single user or role. In fact it doesn't seem to be PostgreSQL alone. Isn't possible to do something like GRANT SELECT ...