1
vote
1answer
134 views

Order by alphabet and then by numbers

I have records like A5 A4 Z1 B2 C7 C1A C11A B1 B4 I want them to be sorted in this manner A4 A5 B1 B2 B4 C1 C11A C7 Z1 using the ORDER BY clause. I want them to be sorted by alphabets ...
2
votes
1answer
149 views

sorting groups of related rows by average values while keeping the groups together

I'm using PostgreSQL 8.4, but would like a standard SQL solution if possible. Consider the following table. corrmodel=# SELECT * from data limit 1; id | datasubgroup_id | datafile_id | ...
3
votes
3answers
2k views

Slow query on large table with GROUP BY and ORDER BY

I have a table with 7.2 million tuples which looks like this: table public.methods column | type | attributes ...
7
votes
1answer
940 views

How to preserve the original order of elements in an unnested array?

Given the string: 'I think that PostgreSQL is nifty' I would like to operate on the individual words found within that string. Essentially, I have a separate from which I can get word details ...
3
votes
2answers
1k views

Postgres primary key sorted in the reverse order. Will it use the index efficiently?

My Rails database is backed by Postgres database. As you may know, each table in Rails gets assigned a primary key which is of Integer type and is indexed. My list views show records in the reverse ...
0
votes
1answer
131 views

Postgres Client - save table sorting

Is there a Postgres client (for Windows) that can save customized sorting when viewing tables? Obviously I could write and save a query for this, but perhaps there's a client that can do this for me. ...
1
vote
1answer
163 views

Working of window functions and idea window size for window function

I am not able to understand the concept of window functions. How exactly they work and what are the pros and cons of such technique? I have read that using limit and offset is slow but its still ...