Notes on MSSQL's Update:from grammar

In the original: The Update:from grammar of MSSQL

Notes on MSSQL's Update:from grammar

1 --the Update:from Grammar of MSSQL2 --Table b Structure ID, name, Id,memo3 4 5 --the memo of Table B needs to be updated with the same key ID as the a table, the statement is as follows6 7 8 Updateb9 SetMemo=A.nameTen  fromA, b One wherea.ID=b.id A --This is just the update of the B result set from within, equivalent to the following sql: - UpdateBSetMemo=(Select Max(A.name) fromAwherea.ID=b.id) - where exists(Select 1    fromAwherea.ID=b.id); the --in fact, all two statements require that the name and ID be one by one, and the ID is the main code. 

Notes on MSSQL's Update:from grammar