I have a need to concatenate strings in the same field based on id in Informix. I realize this can be done easily in MSSQL.
Here is an example of my current table:
id | doc_num | page_num | description
-------------------------------------------------
1 | 1 | 1 | This is the story about
1 | 1 | 2 | a girl named Daisy.
1 | 2 | 1 | Daisy had a dog named
1 | 2 | 2 | Rover.
2 | 1 | 1 | This story is about Bob.
2 | 2 | 1 | Bob is a DBA who works
2 | 2 | 2 | at an important company
2 | 2 | 3 | that develops important
2 | 2 | 4 | software.
Desired output:
id | description
------------------------------------------------------------
1 | This is a story about a girl named Daisy.
| Daisy has a dog named Rover.
------------------------------------------------------------
2 | This story is about Bob. Bob is a DB who works at an
| important company that develops important software.
------------------------------------------------------------
I found my answer here:
https://dba.stackexchange.com/questions/65101/multiple-table-rows-in-one-row-informix
Since I am running Informix 12, it works using rank() over() sys_connect_by_path().
Related
I need help with updating table from another table in Postgres Db.
Long story short we ended up with corrupted data in db, and now I need to update one table with values from another.
I have table with this data table wfc:
| step_id | command_id | commands_order |
|---------|------------|----------------|
| 1 | 1 | 0 |
| 1 | 2 | 1 |
| 1 | 3 | 2 |
| 1 | 4 | 3 |
| 1 | 1 | 0 |
| 2 | 2 | 0 |
| 2 | 3 | 1 |
| 2 | 3 | 1 |
| 2 | 4 | 3 |
and I want to update values in command_order column from another table, so I can have result like this:
| step_id | command_id | commands_order|
|---------|------------|---------------|
| 1 | 1 | 0 |
| 1 | 2 | 1 |
| 1 | 3 | 2 |
| 1 | 4 | 3 |
| 1 | 1 | 4 |
| 2 | 2 | 0 |
| 2 | 3 | 1 |
| 2 | 3 | 2 |
| 2 | 4 | 3 |
It was looking like easy task, but problem is to update rows for same command_id, it is writing same value in commands_order
SQL that I tried is:
UPDATE wfc
SET commands_order = CAST(sq.input_step_id as INTEGER)
FROM (
SELECT wfp.step_id, wfp.input_command_id, wfp.input_step_id
from wfp
order by wfp.step_id, wfp.input_step_id
) AS sq
WHERE (wfc.step_id=sq.step_id AND wfc.command_id=CAST(sq.input_command_id as INTEGER));
SQL Fiddle http://sqlfiddle.com/#!15/4efff4/4
I am pretty stuck with this, please help.
Thanks in advance.
Assuming you are trying to number the rows in the order in which they were created, and as long as you understand that ctid will chnage on update and with VACCUUM FULL, you can do the following:
select step_id, command_id, rank - 1 as command_order
from (select step_id, command_id, ctid as wfc_ctid, rank() over
(partition by step_id order by ctid)
from wfc) as wfc_ordered;
This will give you the wfc table with the ordering that you want. If you do update the original table, the ctids will change, so it's probably safer to create a copy of the table with the above query.
I am new at DynamoDB, in my current project, I am trying to migrate most relational tables to Dynamo DB. I am facing a tricky scenario which I don't know how to solve
In Posgresql, 2 tables:
Student
id | name | age | address | phone
---+--------+-----+---------+--------
1 | Alex | 18 | aaaaaa | 88888
2 | Tome | 19 | bbbbbb | 99999
3 | Mary | 18 | ccccc | 00000
4 | Peter | 20 | dddddd | 00000
Registration
id | class | student | year
---+--------+---------+---------
1 | A1 | 1 | 2018
2 | A1 | 3 | 2018
3 | A1 | 4 | 2017
4 | B1 | 2 | 2018
My query:
select s.id, s.name, s.age, s.address, s.phone
from Registration r inner join Student s on r.student = s.id
where r.class = 'A1' and r.year = '2018'
Result:
id | name | age | address | phone
---+--------+-----+---------+--------
1 | Alex | 18 | aaaaaa | 88888
3 | Mary | 18 | ccccc | 00000
So, how can I design the dynamoDB table to achieve this result? in extend for CRUD
Any advice is appreciated
DynamoDB table design is going to depend largely on your access patterns. Without knowing the full requirements and queries needed by your app, it's not going to be possible to write a proper answer. But given your example here's a table design that might work:
| (GSI PK) |
(P. Key) | (Sort) | (GSI Sort)
studentId | itemType | name | age | address | phone | year
----------+----------+--------+-----+---------+-------+------
1 | Details | Alex | 18 | aaaaaa | 88888 |
1 | Class_A1 | | | | | 2018
2 | Details | Tome | 19 | bbbbbb | 99999 |
2 | Class_B1 | | | | | 2018
3 | Details | Mary | 18 | ccccc | 00000 |
3 | Class_A1 | | | | | 2018
4 | Details | Peter | 20 | dddddd | 00000 |
4 | Class_A1 | | | | | 2017
Note the global secondary index with the partition key on the item type and the sort key on the year.
With this design we have a few query options:
1) Get student for a given id: GetItem(partitionKey: studentId, sortkey: Details)
2) Get all classes for a given student id: Query(partitionKey: studentId, sortkey: STARTS_WITH("Class"));
3) Get all students in class A1 and year 2018: Query(GSI partitionkey: "Class_A1", sortkey: equals(2018))
For global secondary indexes, the partition and sort key don't need to be unique therefore you can have many Class_A1, 2018 combos. If you haven't already read the Best Practices for DyanmoDB I highly recommend reading it in full.
using postgresql 9.3 I have a table that shows indivual permits issued across a single year below:
permit_typ| zipcode| address| name
-------------+------+------+-----
CONSTRUCTION | 20004 | 124 fake streeet | billy joe
SUPPLEMENTAL | 20005 | 124 fake streeet | james oswald
POST CARD | 20005 | 124 fake streeet | who cares
HOME OCCUPATION | 20007 | 124 fake streeet | who cares
SHOP DRAWING | 20009 | 124 fake streeet | who cares
I am trying to flatten this so it looks like
CONSTRUCTION | SUPPLEMENTAL | POST CARD| HOME OCCUPATION | SHOP DRAWING | zipcode
-------------+--------------+-----------+----------------+--------------+--------
1 | 2 | 3 | 5 | 6 | 20004
1 | 2 | 3 | 5 | 6 | 20005
1 | 2 | 3 | 5 | 6 | 20006
1 | 2 | 3 | 5 | 6 | 20007
1 | 2 | 3 | 5 | 6 | 20008
have been trying to use Crosstab but its a bit above my rusty SQL experiance. anybody have any ideas
I usually approach this type of query using conditional aggregation. In Postgres, you can do:
select zipcode,
sum( (permit_typ = 'CONSTRUCTION')::int) as Construction,
sum( (permit_typ = 'SUPPLEMENTAL')::int) as SUPPLEMENTAL,
. . .
from t
group by zipcode;
I have this situation, I have one offer, and that offer have n number of dates, and n number of options. So I have two additional tables for offer. And third one, which is a price, but price depends of date, and offer. And it is like this:
| | date 1 | date 2 | date 3 |
| offer 1 | price 11 | price 12 | price 13 |
| offer 2 | price 21 | price 22 | price 23 |
| offer 3 | price 31 | price 32 | price 33 |
Is there any way to create TCA custom field to insert all of this Price values at once?
So, basically I need one table with input fields and to store also uid of date and offer in it as reference.
Make more than one table... Tables with dynamic col count are horrible bad to maintain.
Table Offer:
uid | Name | Desc
1 | offer1 | This is some cool shit
2 | offer2 | dsadsad
3 | offer3 | sdadsdsadsada
Table Date:
uid | date
1 | 12.02.2014
2 | 12.03.2014
3 | 20.03.2014
Table Prices:
uid | date | offer | price
1 | 1 | 1 | price11
2 | 1 | 2 | price21
3 | 1 | 3 | price31
4 | 2 | 1 | price12
5 | 2 | 2 | price22
6 | 2 | 3 | price32
7 | 3 | 1 | price13
8 | 3 | 2 | price23
9 | 3 | 3 | price33
And then its straight forward...
I need to list all the cities you can get to after stopping off at exactly one other city, starting off from any city of my choice. And list with it the distance to the final city and the intermediate city.
The tables in the database consist of cities, with the attributes:
| city_id | name |
1 Edinburgh
2 Newcastle
3 Manchester
citypairs:
| citypair_id | city_id |
1 1
1 2
2 1
2 3
3 2
3 3
and distances:
| citypair_id | distance |
1 1234
2 1324
3 1324
and trains:
| train_id | departure_city_id | destination_city_id |
1 1 2
2 2 3
3 1 3
4 3 2
I haven't put any of the data in but basically if a city.name is chosen at random by me I need to find out which cities I can get to from this city if I go via another city (i.e. in two journeys) and then the distance to the final and intermediate city.
How would you, or how should I, go about forming a query to return the desired table?
Edited to include data and a missing table! As an example you can go from Edinburgh(1) to Manchester(3) via Newcastle(2) and you can go from Edinburgh to Newcastle via Manchester, however you can not go from Manchester to Edinburgh via Newcastle (since a train departs from 3, arrives at 2, but no train from 2 arrives in 1) and this route should not be returned from the query. Apologies for any confusion beforehand.
I've got a CTE that builds a tree of all the destinations.
WITH RECURSIVE trip AS (
SELECT c.city_id AS start_city,
ARRAY[c.city_id] AS route,
cast(c.name AS varchar(100)) AS route_text,
c.city_id AS leg_start_city,
c.city_id AS leg_end_city,
0 AS trip_count,
0 AS leg_length,
0 AS total_length
FROM cities c
UNION ALL
SELECT
trip.start_city,
trip.route || t.destination_city_id,
cast(trip.route_text || ',' || c.name AS varchar(100)),
t.departure_city_id,
t.destination_city_id,
trip.trip_count + 1,
d.distance,
trip.total_length + d.distance
FROM trains t
INNER JOIN trip
ON t.departure_city_id = trip.leg_end_city
INNER JOIN citypairs cps
ON t.departure_city_id = cps.city_id
INNER JOIN citypairs cpe
ON t.destination_city_id = cpe.city_id AND
cpe.citypair_id = cps.citypair_id
INNER JOIN distances d
ON cps.citypair_id = d.citypair_id
INNER JOIN cities c
ON t.destination_city_id = c.city_id
WHERE NOT (array[t.destination_city_id] <# trip.route))
SELECT *
FROM trip
WHERE trip_count = 2
AND start_city = (SELECT city_id FROM cities WHERE name = 'Edinburgh');
The CTE starts from each city (in the non-recursive part at the start), then determines all the destination cities it can go to. It keeps a track of all the cities its been to in an array (the route column), so it won't loop back to itself again. As it progresses, it keeps track of the overall trip distance, and the number of trains taken (in trip_count).
As it goes through the tree, it keeps a running total of the distance.
This gives results of
| START_CITY | ROUTE | ROUTE_TEXT | LEG_START_CITY | LEG_END_CITY | TRIP_COUNT | LEG_LENGTH | TOTAL_LENGTH |
--------------------------------------------------------------------------------------------------------------------------------
| 1 | 1,2,3 | Edinburgh,Newcastle,Manchester | 2 | 3 | 2 | 1324 | 2558 |
| 1 | 1,3,2 | Edinburgh,Manchester,Newcastle | 3 | 2 | 2 | 1324 | 2648 |
If you change remove the final WHERE clause it'll show all the possible trips in the data, likewise you can change the trip_count to find all single train destinations etc.
| START_CITY | ROUTE | ROUTE_TEXT | LEG_START_CITY | LEG_END_CITY | TRIP_COUNT | LEG_LENGTH | TOTAL_LENGTH |
--------------------------------------------------------------------------------------------------------------------------------
| 1 | 1 | Edinburgh | 1 | 1 | 0 | 0 | 0 |
| 2 | 2 | Newcastle | 2 | 2 | 0 | 0 | 0 |
| 3 | 3 | Manchester | 3 | 3 | 0 | 0 | 0 |
| 1 | 1,2 | Edinburgh,Newcastle | 1 | 2 | 1 | 1234 | 1234 |
| 1 | 1,3 | Edinburgh,Manchester | 1 | 3 | 1 | 1324 | 1324 |
| 2 | 2,3 | Newcastle,Manchester | 2 | 3 | 1 | 1324 | 1324 |
| 3 | 3,2 | Manchester,Newcastle | 3 | 2 | 1 | 1324 | 1324 |
| 1 | 1,2,3 | Edinburgh,Newcastle,Manchester | 2 | 3 | 2 | 1324 | 2558 |
| 1 | 1,3,2 | Edinburgh,Manchester,Newcastle | 3 | 2 | 2 | 1324 | 2648 |
The cast( ... as varchar(100)) is a bit hacky, and I'm not sure why it was needed, but I haven't had a chance to get around that yet.
The SQL is here for testing: http://sqlfiddle.com/#!1/93964/24
The first part is easy:
SELECT c2.name
FROM cities AS c
JOIN trains t ON c.city_id=t.departure_city_id
JOIN trains t2 ON t.destination_city_id=t2.departure_city_id
JOIN cities AS c2 ON t2.destination_city_id=c2.city_id
WHERE c2.city_id!=c.city_id
AND c.name='Edinburgh';
http://sqlfiddle.com/#!12/a656f/14
In PG 9.1+ you could even do it with a recursive CTE for any number of cities in between. The distances are a little more complicated and you probably would be better off transforming city_pairs into actual pairs.