SQL Server 2019

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CREATE TABLE PersonsInitial (
    tel varchar(255),
    firstname varchar(255),
    lastname varchar(255)
);

insert into PersonsInitial(tel,firstname,lastname) values
('+41/ jfakl2 eaf3efa54844','Manu','Johns'),
('01-afe fa-e8fa5a +e5+ e+234','Fernand','Wajk'),
(' +41/34 jfakl2 eaf3efa54844','Fred','Johns')

;

select tel, firstname, lastname from PersonsInitial

--if there is a person with the same tel number chose the customer id with 'C'
--if I don't have the choice add the customer without C

CREATE TABLE PersonsFinal (
    tel varchar(255),
    firstname varchar(255),
    lastname varchar(255))
;

insert into PersonsFinal(tel,firstname,lastname) values
('00412354844','Manu','Johns'),
('01855234','Fernand','Wajk'),
('0041342354844','Fred','Johns')

;
select tel, firstname, lastname from PersonsFinal


tel
firstname
lastname


+41/ jfakl2 eaf3efa54844
Manu
Johns

01-afe fa-e8fa5a +e5+ e+234
Fernand
Wajk

 +41/34 jfakl2 eaf3efa54844
Fred
Johns




tel
firstname
lastname


00412354844
Manu
Johns

01855234
Fernand
Wajk

0041342354844
Fred
Johns


declare @replace varchar(30)='abcdefghijklmnopqrstuvwxyz/+-';
select * , Replace(Translate(Iif(Left(Replace(tel,' ',''),1)='+',Concat('00',tel),tel), @replace, Replicate(' ',Len(@replace))),' ','')
from PersonsInitial;


tel
firstname
lastname
(No column name)


+41/ jfakl2 eaf3efa54844
Manu
Johns
00412354844

01-afe fa-e8fa5a +e5+ e+234
Fernand
Wajk
01855234

 +41/34 jfakl2 eaf3efa54844
Fred
Johns
0041342354844


declare @replace varchar(30)='abcdefghijklmnopqrstuvwxyz/+-';
with fixy as (
select * , Replace(Translate(Iif(Left(Replace(tel,' ',''),1)='+',Concat('00',tel),tel), @replace, Replicate(' ',Len(@replace))),' ','') newTel
from PersonsInitial
)
update fixy set tel=newTel;
3 rows affected

select * from PersonsInitial;


tel
firstname
lastname


00412354844
Manu
Johns

01855234
Fernand
Wajk

0041342354844
Fred
Johns

tel	firstname	lastname
+41/ jfakl2 eaf3efa54844	Manu	Johns
01-afe fa-e8fa5a +e5+ e+234	Fernand	Wajk
+41/34 jfakl2 eaf3efa54844	Fred	Johns

tel	firstname	lastname
00412354844	Manu	Johns
01855234	Fernand	Wajk
0041342354844	Fred	Johns