How to create incrementing columns? - oracle

Question

I have table with these column names.
Province/State
Country/Region
Lat
Long
1/22/20
1/23/20
1/24/20
1/25/20
...
...
3/21/20
I know to create first 4 columns but I don't know how create date column and increment it.
How can I implement such number of columns at once?
Thank you!
Infected
Dead
Recovered
Object relational data model created by me
Question -: Submit working Oracle script for your database schema.

Answer 1

Don't try to create a column-per-day; just create a table with columns for location, date and for each statistic (i.e. infected, recovered, dead, etc.) and then if you need to pivot them do that in a query (or in whatever middle-tier application [i.e. PHP, Java, .net] you're using to access the database).
Something like:
CREATE TABLE Regions(
id VARCHAR2(6)
CONSTRAINT regions__id__pk PRIMARY KEY,
parent_id VARCHAR2(6)
CONSTRAINT regions_parent__fk REFERENCES Regions ( id ),
name VARCHAR2(50)
CONSTRAINT regions__name__nn NOT NULL
CONSTRAINT regions__name__u UNIQUE,
latitude NUMBER
CONSTRAINT regions__lat__nn NOT NULL,
longitude NUMBER
CONSTRAINT regions__long__nn NOT NULL,
CONSTRAINT regions__id__chk CHECK (
( parent_id IS NULL AND REGEXP_LIKE( id, '^[A-Z]{2}$' ) )
OR ( parent_id IS NOT NULL AND REGEXP_LIKE( id, '^[A-Z]{2}-[A-Z0-9]{1,3}$' ) )
)
);
COMMENT ON COLUMN Regions.id IS 'ISO 3166-2 Alpha-2 Country Code or ISO 3166-2 Province Code';
COMMENT ON COLUMN Regions.name IS 'ISO 3166-2 English Short Name.';
COMMENT ON COLUMN Regions.latitude IS 'Latitude of the region''s main city.';
COMMENT ON COLUMN Regions.longitude IS 'Longitude of the region''s main city.';
CREATE TABLE Virus_Statistics(
id NUMBER(20,0)
GENERATED ALWAYS AS IDENTITY
CONSTRAINT virus_statistics__id__pk PRIMARY KEY,
location VARCHAR2(6)
CONSTRAINT virus_statistics__loc__nn NOT NULL
CONSTRAINT virus_statistics__loc__fk REFERENCES Regions ( id ),
datetime DATE
CONSTRAINT virus_statistics__dt__nn NOT NULL
CONSTRAINT virus_statistics__dt__chk CHECK ( datetime = TRUNC( datetime ) ),
infected NUMBER(10,0),
recovered NUMBER(10,0),
dead NUMBER(10,0),
CONSTRAINT virus_statistics__loc__dt__u UNIQUE ( location, datetime )
);
Then you can input your data. For example, the regions would be:
INSERT INTO Regions ( id, parent_id, name, latitude, longitude )
SELECT 'TH', NULL, 'Thailand', 15.00000, 101.00000 FROM DUAL UNION ALL
SELECT 'JP', NULL, 'Japan', 36.00000, 138.00000 FROM DUAL UNION ALL
SELECT 'SG', NULL, 'Singapore', 1.28333, 103.83333 FROM DUAL UNION ALL
SELECT 'NP', NULL, 'Nepal', 28.16667, 84.25000 FROM DUAL UNION ALL
SELECT 'MY', NULL, 'Malaysia', 2.50000, 112.50000 FROM DUAL UNION ALL
SELECT 'CA', NULL, 'Canada', 45.42472, - 75.69500 FROM DUAL UNION ALL
SELECT 'CA-BC', 'CA', 'British Columbia', 48.40733, -123.32977 FROM DUAL;
And the first 3 columns of data would be:
INSERT INTO Virus_Statistics ( location, datetime, infected, recovered, dead )
SELECT 'TH', DATE '2020-01-22', 2 AS i, 0 AS r, 0 AS d FROM DUAL UNION ALL
SELECT 'TH', DATE '2020-01-23', 3, 0, 0 FROM DUAL UNION ALL
SELECT 'TH', DATE '2020-01-24', 5, 0, 0 FROM DUAL UNION ALL
SELECT 'JP', DATE '2020-01-22', 2, 0, 0 FROM DUAL UNION ALL
SELECT 'JP', DATE '2020-01-23', 1, 0, 0 FROM DUAL UNION ALL
SELECT 'JP', DATE '2020-01-24', 2, 0, 0 FROM DUAL UNION ALL
SELECT 'SG', DATE '2020-01-22', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'SG', DATE '2020-01-23', 1, 0, 0 FROM DUAL UNION ALL
SELECT 'SG', DATE '2020-01-24', 3, 0, 0 FROM DUAL UNION ALL
SELECT 'NP', DATE '2020-01-22', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'NP', DATE '2020-01-23', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'NP', DATE '2020-01-24', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'MY', DATE '2020-01-22', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'MY', DATE '2020-01-23', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'MY', DATE '2020-01-24', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'CA-BC', DATE '2020-01-22', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'CA-BC', DATE '2020-01-23', 0, 0, 0 FROM DUAL UNION ALL
SELECT 'CA-BC', DATE '2020-01-24', 0, 0, 0 FROM DUAL;
Then if you want to output it as columns-per-day then use a PIVOT:
SELECT *
FROM (
SELECT name,
latitude,
longitude,
datetime,
infected
FROM Virus_Statistics v
INNER JOIN Regions r
ON ( r.id = v.location )
)
PIVOT (
MAX( infected )
FOR datetime IN (
DATE '2020-01-22' AS "2020-01-22",
DATE '2020-01-23' AS "2020-01-23",
DATE '2020-01-24' AS "2020-01-24"
)
)
Which outputs:
NAME | LATITUDE | LONGITUDE | 2020-01-22 | 2020-01-23 | 2020-01-24
:--------------- | -------: | ---------: | ---------: | ---------: | ---------:
Japan | 36 | 138 | 2 | 1 | 2
Malaysia | 2.5 | 112.5 | 0 | 0 | 0
Singapore | 1.28333 | 103.83333 | 0 | 1 | 3
Nepal | 28.16667 | 84.25 | 0 | 0 | 0
British Columbia | 48.40733 | -123.32977 | 0 | 0 | 0
Thailand | 15 | 101 | 2 | 3 | 5
db<>fiddle here