sql - Does multi-row multi update vs many updates statement works exactly the same? [PosgreSQL] -

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i can't seem find resources addressing this, 

update "my-table" t     set "val"=v."val",         "msg"=v."msg"  (    values(1,123,'hello'),          (2,456,'world!') ) v("id","val","msg")  v.id = t.id

vs

update "my-table"      set val = 123, msg = 'hello'  id = 1;  update "my-table"      set val = 456, msg = 'world'  id = 2;

what interested in whether concurrency control between each case same read committed isolation level?

after reading feel quite safe how handles update concurrently https://www.postgresql.org/docs/current/static/transaction-iso.html#xact-read-committed

begin; update accounts set balance = balance + 100.00 acctnum = 12345; update accounts set balance = balance - 100.00 acctnum = 7534; commit;

but there no mentioning multi value update , how behaves?


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