Tagged Questions
0
votes
1answer
16 views
SELECT several columns based on one condition
Is there a way to generate more then one column based on one condition? My perception is like:
SELECT
CASE WHEN condition_column = 'condition true' and (condition_column2 = 'condition true' or ...
5
votes
1answer
2k views
Make a range in postgres
How can I make a range in a select in PostgreSQL? I'd like to have this result:
num
---
1
2
3
4
5
6
From a query like:
SELECT range(1,6) AS num;
0
votes
3answers
28 views
Postgres: Distinct but only for one column
I have a table on pgsql with names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id, name, metadata.
I want to select them randomly with ORDER BY RANDOM() and ...
0
votes
5answers
53 views
Relational algebra: select only last try
consider this database table :
table: score(player_name,player_lastname,try,score)
primary key: (player_name,player_lastname,try)
(dont discuss the table schema, its just an example)
this table hold ...
0
votes
1answer
41 views
more than one row returned by a subquery used as an expression postgresql
postgresql, I have a table my_table 4 table that has columns stxstxid, stxuserid sumamountstx, userid, amountcredit, amountsrc
My goal is to merge different rows that have the same stxstxid, ...
2
votes
4answers
74 views
Joining tables if the reference exists
I got a PostgreSQL database with 4 tables:
Table A
---------------------------
| ID | B_ID | C_ID | D_ID |
---------------------------
| 1 | 1 | NULL | NULL |
---------------------------
| 2 | ...
0
votes
5answers
29 views
Operations on selected items
I want to have query like this:
SELECT
sum(data_parts.size) as size_sum,
(size_sum/2.) as half_of_size_sum
FROM
data_parts
WHERE
data_parts.some_id='1';
Of course it won't work, because ...
0
votes
1answer
27 views
postgreSQL max select depending on groups
I am facing a particularly difficult (for my skill level) select query.
I have some data in a database which are as such:
4 columns (maleName/femaleName/size/id).
The column data are more or less ...
0
votes
4answers
49 views
postgresql: how to SELECT entries that satisfy a condition
I am trying to select the entries that have the same text in the "email" column of my postgreSQL table. I am completly new to database and this is the first database I ever created, so sorry if it's a ...
2
votes
3answers
139 views
How to re-use result for SELECT, WHERE and ORDER BY clauses?
The following query returns the venues near us (lat: 62.0, lon: 25.0) inside whose radius we fall in ordered by distance:
SELECT *,
earth_distance(ll_to_earth(62.0, 25.0),
...
1
vote
2answers
39 views
Divide records into groups - quick solution
I need to divide with UPDATE command rows (selected from subselect) in PostgreSQL table into groups, these groups will be identified with integer value in one of its columns. These groups should be ...
1
vote
2answers
1k views
Postgresql SELECT random with unique value
I am not able to make one clean SELECT
I have postgresql table with fields
id , providerid, deal_name
I want to make random select with unique providerid
SELECT * FROM deals ORDER BY random() ...
4
votes
5answers
84 views
Select unique count of rows referenced
High level:
I have checklists and checklists have checklist items. I want get the count of checklists that been completed. Specifically, checklists that have checklist items but that are all ...
0
votes
3answers
59 views
finding the latest entry in Postgres
The following (Postgres) query always returns a result, because the performance.query_plan table has several entries, with different ts (Timestamp) values.
select * from
performance.query q,
...
0
votes
1answer
70 views
Update table using data from other tables (normalization)
I have doubt to mount a query to update and / or add data in a table.
I have a table1 that will be supplied with the following rules:
The table1 have the same fields of table2 + status field to show ...
