how to scatter multiple duplicate rows into one row in sql/postgresql.
For example --->
lets i am getting 3 rows of
col1 col2 col3
-------------------
11 test rat
11 test cat
11 test test
I want something like this
col1 col2 col3 col4
------------------------
11 test rat cat
Its the same thing like groupby in lodash. But how do I achieve the same in postgresql query?
You're looking for crosstab
postgres=# create table ab (col1 text, col2 text, col3 text);
CREATE TABLE
postgres=# insert into ab values ('t1','test','cat'),('t1','test','rat'),('t1','test','test');
INSERT 0 3
postgres=# select * from crosstab('select col1,col2,col3 from ab') as (col1 text, col2 text, col3 text, col4 text);
col1 | col2 | col3 | col4
------+------+------+------
t1 | cat | rat | test
(1 row)
Disclosure: I work for EnterpriseDB (EDB)
Related
Does MINUS/EXCEPT command or code workaround analog exist for columns only? Since MINUS/EXCEPT command fine for rows, how about for columns?
Mask-table (physically exist):
id col1 col2 col3 col4 ... colN comment
doesn't A B C D ... Z --alphabet correct sequence
matter
Columns Data Type of col[i] equals to each other.
Incoming select-stream (not a physical table, but represented as table as a result of other complex joined-selection from other tables):
col1 col2 col3 col4 ... colN comment
A B C D ... Z --alphabet correct seq
A C B D ... Z --incorrect
E B C M ... Z --incorrect
...
Z Y X W ... A --full inverse icorrect
Expected output to physical table after processing mask-table to select-stream as insert result:
id col1 col2 col3 col4 ... colN
(auto-
gnrtd)
(null)(null)(null)(null)...(null)
(null) C B (null)...(null)
E (null)(null) M ...(null)
...
Z Y X W ... A
Please note: alphabet is given just as an example. Not the issue-case here. SQL-Logic/command required. Analog of MINUS/EXCEPT, but for columns (DISTINCT? How, if incoming select-stream is a result of other complex joined-select)
What will be the SQL-code for this task? Please, advise.
Another way to do it without CASE statements:
Setup
CREATE TABLE mask (
col1 TEXT,
col2 TEXT,
col3 TEXT,
col4 TEXT,
col5 TEXT
);
INSERT INTO mask SELECT 'A', 'B', 'C', 'D', 'E';
CREATE TABLE your_stream (
col1 TEXT,
col2 TEXT,
col3 TEXT,
col4 TEXT,
col5 TEXT
);
INSERT INTO your_stream
VALUES
('A', 'B', 'C', 'D', 'E'),
('A', 'C', 'B', 'D', 'E'),
('E', 'B', 'C', 'M', 'E');
Query
SELECT
NULLIF(s.col1, m.col1) AS col1,
NULLIF(s.col2, m.col2) AS col2,
NULLIF(s.col3, m.col3) AS col3,
NULLIF(s.col4, m.col4) AS col4,
NULLIF(s.col5, m.col5) AS col5
FROM your_stream s
CROSS JOIN mask m;
Result
| col1 | col2 | col3 | col4 | col5 |
| ---- | ---- | ---- | ---- | ---- |
| null | null | null | null | null |
| null | C | B | null | null |
| E | null | null | M | null |
View on DB Fiddle
I don't see what the connection to a set operation like EXCEPT would be.
Anyway, this is how you could proceed:
INSERT INTO destination (col1, col2, col3, ...)
SELECT CASE WHEN incoming_col1 <> mask.col1
THEN incoming_col1
END,
CASE WHEN incoming_col2 <> mask.col2
THEN incoming_col2
END,
...
FROM mask;
I have the table
| Col1 | Col2 | Col3 |
I want a new table with these values
| Col4 | Col5 | Col2 | Col6 |
With any values of col2 onto the new table
Thanks!
If It Is Just About To Import All Data Of Col2 In Another Table ,Then
Suppose TB1 has Columns (Col1 , Col2 , Col3)
and TB2 has Columns (Col4 , Col5 , Col2 , Col6)
Then Your Quert Would Be Like This ,
Insert INTO TB2(Col2)(Select Col2 From TB1);
else
Please Give More Specification Like You Want To Update Data That is Not In TB2 Like That.
I have three columns in a table.
Requirements: The value of col2 and col3 should make col1.
Below shows the table I have right now, which needs to be change.
col1 col2 col3
AB football
AB football
ER driving
ER driving
TR city
TR city
Below shows the table that needs to be change to
col1 col2 col3
AB_football_1 AB football
AB_football_2 AB football
ER_driving_1 ER driving
ER_driving_2 ER driving
TR_city_1 TR city
TR_city_2 TR city
As you can see in col1, it should take col2, put (underscore), then col3, put (underscore) then increment the number according to the values in col2 and col3.
Can this be approached within CREATE or SELECT or INSERT statement or Trigger Statement, if so any tips would be grateful.
Try as
SELECT col2
||'_'
||col3
||'_'
||rank col1,
col2,
col3
FROM (SELECT col2,
col3,
ROW_NUMBER()
OVER(
PARTITION BY col2, col3
ORDER BY col2) rank
FROM my_table)
Output
+---------------+------+----------+
| COL1 | COL2 | COL3 |
+---------------+------+----------+
| AB_football_1 | AB | football |
| AB_football_2 | AB | football |
| ER_driving _1 | ER | driving |
| ER_driving _2 | ER | driving |
| TR_city _1 | TR | city |
| TR_city _2 | TR | city |
+---------------+------+----------+
/* table is */
col1 col2 col3
test 123
/* Try this query */
UPDATE `demo`
SET `col1` = concat(col2, '_', col3)
/* Output will be */
col1 col2 col3
test_123 test 123
This is easy to do (at SELECT) using row_number() window function , something like this:
select
col2 ||'_'|| col3 ||'_'|| row_number() over(partition by col2, col3 order by col2) as col1,
col2,
col3
from t
I am trying to come up with a trigger that fills a column of a row that I insert/update with a score that depends on the the numeric values on other columns of that same row.
For example
+------+------+------+------+------+------+
| col1 | col2 | col3 | col4 | col5 | col6 |
+------+------+------+------+------+------+
| 1 | 2 | 1 | 3 | 1 | |
+------+------+------+------+------+------+
This is the row I want to insert, I would like to fill col6 with a score calculated using the values of the other columns
(100 - avg(col1:col5)/4*100)
Can I do this through a trigger or procedure? Should I do this before or after the insert?
From Oracle 11g you can use a virtual column:
Oracle Setup:
CREATE TABLE table_name (
col1 NUMBER,
col2 NUMBER,
col3 NUMBER,
col4 NUMBER,
col5 NUMBER,
col6 NUMBER GENERATED ALWAYS AS ( 100 - (col1+col2+col3+col4+col5)*5 ) VIRTUAL
);
INSERT INTO table_name ( col1, col2, col3, col4, col5 )
VALUES ( 1, 2, 1, 3, 1 );
Query:
SELECT * FROM table_name;
Output:
COL1 COL2 COL3 COL4 COL5 COL6
---- ---- ---- ---- ---- ----
1 2 1 3 1 60
A trigger would look like.
CREATE OR REPLACE TRIGGER ti
BEFORE UPDATE OR INSERT ON yourtable
FOR EACH ROW
BEGIN
:new.col6 :=
( 100
- (:new.col1 + :new.col2 + :new.col3 + :new.col4 + :new.col5)/ 5 * 100);
end;
I did it this way to avoid the possible null values that might exist. Thank you all for the precious help.
create or replace TRIGGER SCORE_SYMP_TRG
BEFORE INSERT OR UPDATE ON KOOS
FOR EACH ROW
DECLARE
BEGIN
:NEW.SCORE_SYMP := 100 - ROUND(((NVL(:NEW.S1,0) + NVL(:NEW.S2,0) + NVL(:NEW.S3,0) + NVL(:NEW.S4,0) + NVL(:NEW.S5,0) + NVL(:NEW.R6, 0) + NVL(:NEW.R7, 0))/(
NVL((NVL(:NEW.S1,0)/NVL(:NEW.S1,1)),0) + NVL((NVL(:NEW.S2,0)/NVL(:NEW.S2,1)),0) + NVL((NVL(:NEW.S3,0)/NVL(:NEW.S3,1)),0) + NVL((NVL(:NEW.S4,0)/NVL(:NEW.S4,1)),0)
+ NVL((NVL(:NEW.S5,0)/NVL(:NEW.S5,1)),0) + NVL((NVL(:NEW.R6,0)/NVL(:NEW.R6,1)),0) + NVL((NVL(:NEW.R7,0)/NVL(:NEW.R7,1)),0)) /4)*100,0);
END;
My Table data looks like
Col1 | Col2 | Col3
1 | NULL | NULL
NULL | 2 | NULL
NULL | NULL | 3
It is given that for any column there will be only entry. This means that, in the above data, if row1 has value for Col1, then there will be no row with value for Col1. Similarly, if row1 has value for Col1, it will not have value for any other column.
I want to write a query, so that I get only one row out for entire data (leaving NULL values). ie.
Col1 | Col2 | Col3
1 | 2 | 3
The easiest way to do this is using aggregation:
select max(col1) as col1, max(col2) as col2, max(col3) as col3
from t;
select
sum(ifnull(col1,0)) as col1,
sum(ifnull(col2,0)) as col2
sum(ifnull(col3,0)) as col3
from t;
Assuming the table is called tab the following query will work if there are only 3 columns:
select t1.Col1, t2.Col2, t3.Col3
from tab t1, tab t2, tab t3
where t1.Col1 is not null and t2.Col2 is not null and t3.Col3 is not null
The problem is the query will have to alias the table for each additional column. It may not be perfect, but it is a solution.