Postgres 12

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select version();


version


PostgreSQL 12.3 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.3.1 20191121 (Red Hat 8.3.1-5), 64-bit


create table test( column_b text
                 , column_a integer
                 , column_c text
                 , column_d text);
                
insert into test(column_b, column_a,column_c, column_d) 
values ('123',null,'xyz','cold #1')
     , ('345',   2,'abc','cold #2')
     , ('789',  13,'def','cold #3');
3 rows affected

select * from test order by column_b; 


column_b
column_a
column_c
column_d


123
null
xyz
cold #1

345
2
abc
cold #2

789
13
def
cold #3


update test t
    set column_a = c.column_a
      , column_c = c.column_c 
 from (values ('123', 1, NULL, 'Ignored Column')
            , ('345', NULL, '+++','Ignored Column')  
      ) c(column_b, column_a, column_c,column_d) 
where c.column_b = t.column_b ;
2 rows affected

select * from test order by column_b; 


column_b
column_a
column_c
column_d


123
1
null
cold #1

345
null
+++
cold #2

789
13
def
cold #3