I'm trying to write a query that will list the columns in a table when 3 specific fields are the same, but unknown:
TABLE:
FIELD 1 | FIELD 2 | FIELD 3 | FIELD 4
---------|--------------|------------|---------------
1 | 01-01-15 | 21 | 150
1 | 01-01-15 | 24 | 12
1 | 02-01-15 | 21 | 681
1 | 01-01-15 | 21 | 299
DESIRED RESULTS:
FIELD 1 | FIELD 2 | FIELD 3 | FIELD 4
-------------|--------------|-------------|------------
1 | 01-01-15 | 21 | 150
1 | 01-01-15 | 21 | 299
Sorry - still a newb here! Thanks in advance!
Count the number of rows with the same combination and filter for a count > 1:
select *
from tab
qualify
count(*)
over (partition by field1, field2, field3) > 1
Related
The first column of a table contains some Ids and the values in the other columns are the numbers corresponded to those Ids. Considering some special numbers, we want to select the rows that this special numbers are among the corresponded numbers to Ids. For example, let we have the following table and the special numbers are 3,5. We want to select the rows in which 2,5 are among the columns except Id:
| Id | corresponded numbers
|----|----------------------
| 1 | 2 | 3 | 5 |
| 2 | 1 | 5 |
| 3 | 1 | 2 | 4 | 5 | 7 |
| 4 | 3 | 5 | 6 |
Therefore, we want to have the following table as the result:
| Id | corresponded numbers
|----|----------------------
| 1 | 2 | 3 | 5 |
| 3 | 1 | 2 | 4 | 5 | 7 |
Would you please introduce me a function in Excel or a query in SQL to do the above selection?
SELECT id,
[corresponded numbers]
FROM TableName
WHERE (charIndex('2', [corresponded numbers]) > 0
AND charIndex('5', [corresponded numbers]) > 0)
I am new to SQL and I would like to ask about how to select entries based on preferences and grouping.
+----------+----------+------+
| ENTRY_ID | ROUTE_ID | TYPE |
+----------+----------+------+
| 1 | 15 | 0 |
| 1 | 26 | 1 |
| 1 | 39 | 1 |
| 2 | 22 | 1 |
| 2 | 15 | 1 |
| 3 | 30 | 1 |
| 3 | 35 | 0 |
| 3 | 40 | 1 |
+----------+----------+------+
With the table above, I would like to select 1 entry for each ENTRY_ID with the following preference for the returned ROUTE_ID:
IF TYPE = 0 is available
for any one of the entries with the same ENTRY_ID, return the minimum ROUTE_ID for all entries with TYPE = 0
IF for the same ENTRY_ID only TYPE = 1 is available, return the minimum ROUTE_ID
The expected outcome for the query will be the following:
+----------+----------+------+
| ENTRY_ID | ROUTE_ID | TYPE |
+----------+----------+------+
| 1 | 15 | 0 |
| 2 | 15 | 1 |
| 3 | 35 | 0 |
+----------+----------+------+
Thank you for your help!
You can group by both TYPE and ENTRY_ID, and then use the HAVING clause to filter out those where TYPE is not the minimal value for that record.
SELECT ENTRY_ID, MIN(ROUTE_ID), TYPE
FROM MyTable
GROUP BY ENTRY_ID, TYPE
HAVING TYPE = (SELECT MIN(s.TYPE) FROM MyTable s WHERE s.ENTRY_ID = MyTable.ENTRY_ID)
This relies on type only being able to be 0 or 1. If there are more possible values, it will only return the lowest type.
If you want complete rows, use a correlated subquery:
select t.*
from t
where t.route_id = (select top 1 t2.route_id
from t as t2
where t2.entry_id = t.entry_id
order by iif(t2.type = 0, 1, 2), -- put type 0 first
t2.route_id asc -- then the first route_id
);
This has the advantage that it can return more than just the three columns you show in the question.
I'm trying to solve the bus routing problem in postgresql which requires visibility of previous and next rows. Here is my solution.
Step 1) Have one edges table which represents all the edges (the source and target represent vertices (bus stops):
postgres=# select id, source, target, cost from busedges;
id | source | target | cost
----+--------+--------+------
1 | 1 | 2 | 1
2 | 2 | 3 | 1
3 | 3 | 4 | 1
4 | 4 | 5 | 1
5 | 1 | 7 | 1
6 | 7 | 8 | 1
7 | 1 | 6 | 1
8 | 6 | 8 | 1
9 | 9 | 10 | 1
10 | 10 | 11 | 1
11 | 11 | 12 | 1
12 | 12 | 13 | 1
13 | 9 | 15 | 1
14 | 15 | 16 | 1
15 | 9 | 14 | 1
16 | 14 | 16 | 1
Step 2) Have a table which represents bus details like from time, to time, edge etc.
NOTE: I have used integer format for "from" and "to" column for faster results as I can do an integer query, but I can replace it with any better format if available.
postgres=# select id, "busedgeId", "busId", "from", "to" from busedgetimes;
id | busedgeId | busId | from | to
----+-----------+-------+-------+-------
18 | 1 | 1 | 33000 | 33300
19 | 2 | 1 | 33300 | 33600
20 | 3 | 2 | 33900 | 34200
21 | 4 | 2 | 34200 | 34800
22 | 1 | 3 | 36000 | 36300
23 | 2 | 3 | 36600 | 37200
24 | 3 | 4 | 38400 | 38700
25 | 4 | 4 | 38700 | 39540
Step 3) Use dijkstra algorithm to find the nearest path.
Step 4) Get the upcoming buses from the busedgetimes table in the earliest first order for the nearest path detected by dijkstra algorithm.
Problem: I am finding it difficult to make the query for the Step 4.
For example: If I get the path as edges 2, 3, 4, to travel from source vertex 2 to target vertex 5 in the above records. To get the first bus for the first edge, it's not so hard as I can simply query with from < 'expected departure' order by from desc but for the second edge, the from condition requires to time of first result row. Also, query requires edge ids filter.
How can I achieve this in a single query?
I am not sure if I understood your problem correctly. But getting values from other rows this can be done by window functions (https://www.postgresql.org/docs/current/static/tutorial-window.html):
demo: db<>fiddle
SELECT
id,
lag("to") OVER (ORDER BY id) as prev_to,
"from",
"to",
lead("from") OVER (ORDER BY id) as next_from
FROM bustimes;
The lag function moves the value of the previous row into the current one. The lead function does the same with the next row. So you are able to calculate a difference between last arrival and current departure or something like that.
Result:
id prev_to from to next_from
18 33000 33300 33300
19 33300 33300 33600 33900
20 33600 33900 34200 34200
21 34200 34200 34800 36000
22 34800 36000 36300
Please notice that "from" and "to" are reserved words in PostgreSQL. It would be better to chose other names.
Yesterday I asked this question: SQL: How to add values according to index columns but I found out that my problem is a bit more complicated:
I have an array like this
id | value| position | relates_to_position |type
19 | 100 | 2 | NULL | 1
19 | 50 | 6 | NULL | 2
19 | 20 | 7 | 6 | 3
20 | 30 | 3 | NULL | 2
20 | 10 | 4 | 3 | 3
From this I need to create the resulting table, which adds all the lines where the relates_to_position value matches the position value, but only for lines sharing the same id!
The resulting table should be
id | value| position |type
19 | 100 | 2 | 1
19 | 70 | 6 | 2
20 | 40 | 3 | 2
I am using Oracle 11. There is only one level of recursion, meaning a line would not refer to a line which has the relates_to_pos field set.
I think the following query will do this:
select id, coalesce(relates_to_position, position) as position,
sum(value) as value, min(type) as type
from t
group by id, coalesce(relates_to_position, position);
I would like to accumulate my data as you can see below there is origin table table1:
What is the best query for to do this?
Is possible to do this dynamically - when I add more types of terms??
Table 1
ID | term | value
-----------------------
1 | I | 100
2 | I | 200
3 | II | 100
4 | II | 50
5 | II | 75
6 | III | 50
7 | III | 65
8 | IV | 30
9 | IV | 45
And the result should be like below:
YTD | Acc Value
------------------
I-I | 300
I-II | 525
I-III| 640
I-IV | 715
Thanks
select
(select min(term) from yourtable ) +'-'+term,
(select sum(value) from yourtable t1 where t1.term<=t.term)
from yourtable t
group by term