PL/SQL procedure to insert id to rows having same information - sql

Question

I have contact details data in Oracle table something like below...
I want to insert new column to assign same ID to the contacts having matching information , i.e. based on group of lastname, firstname and (phone and/or email)
Output should look like below
I'm new to this forum, so having formatting issues while posting question, please see attached images for easy understanding of my requirement
Looking for PL/SQL procedure to get this done in our huge database

Answer 1

Due to the nature of the data you presented I see no possible way to do it in one SQL or for it to be better tuned.
Script to create the table and populate with your example:
create table TAB_TEST(LAST_NAME VARCHAR2(200),
FIRST_NAME VARCHAR2(200),
PHONE NUMBER,
EMAIL VARCHAR2(200))
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 2058371579, 'ABC#GMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 4479940000, 'ABC#GMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7195739945, 'XYZ#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7475393956, 'XYZ#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7475393956, 'XYZ#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7473430336, null)
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7195739945, 'XYZ#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7475393956, '123#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', null, '123#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 1168548666, '456#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 1168548666, '456#HOTMAIL.COM')
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 1168548666, null)
/
INSERT INTO TAB_TEST VALUES
('Ho','Kim', 7473430336, null)
/
ALTER TABLE TAB_TEST ADD ID NUMBER
/
And the script to update
DECLARE
lncount NUMBER := 1;
-- had to create this record in order to add the rowid
TYPE lttab_test IS RECORD(
ROWID VARCHAR2(200),
last_name VARCHAR2(200),
first_name VARCHAR2(200),
phone NUMBER,
email VARCHAR2(200),
id NUMBER);
TYPE lttype
IS TABLE OF LTTAB_TEST;
larecords LTTYPE;
BEGIN
SELECT ROWID,
last_name,
first_name,
phone,
email,
id
bulk collect INTO larecords
FROM tab_test a;
FOR i IN 1..larecords.count LOOP
IF Larecords(i).id IS NULL THEN
FOR j IN 1..i-1 LOOP
IF Larecords(j).phone = Larecords(i).phone
AND Larecords(i).id IS NULL THEN
Larecords(i).id := Larecords(j).id;
exit;
END IF;
END LOOP;
FOR j IN 1..i-1 LOOP
IF Larecords(j).email = Larecords(i).email
AND Larecords(i).id IS NULL THEN
Larecords(i).id := Larecords(j).id;
exit;
END IF;
END LOOP;
IF Larecords(i).id IS NULL THEN
Larecords(i).id := lncount;
lncount := lncount + 1;
END IF;
END IF;
END LOOP;
forall i IN 1..larecords.count
UPDATE tab_test
SET id = Larecords(i).id
WHERE ROWID = Larecords(i).ROWID;
COMMIT:
END;

Answer 2

It isn't the most efficient / pretty code but it works in case you just want sequential numbers
DECLARE
I NUMBER := 0;
BEGIN
ALTER TABLE TABLE
ADD ID NUMBER;
COMMIT;
FOR REC IN (SELECT * FROM TABLE)
LOOP
IF(REC.ID IS NULL) THEN
UPDATE TABLE T SET ID = I
WHERE (T.EMAIL = REC.EMAIL OR T.PHONE = REC.PHONE)
AND ID IS NULL;
COMMIT;
I := I + 1;
END IF;
END LOOP;
END;