SQL Server Update table (data for another table is updated with data from a single table)

A) Easy to type, update efficiency:

Update table1

Set Field1=table2.field1,field2=table2.field2

From Table2 where table1.id=table2.id

b) Conventional way, this is equivalent to a left join, in the outside where is the number of updates, if not add where is all records

Update table1 Set field1=

(select top 1 field1 from table2 where table2.id=table1.id)

where table1.id in (condition)

SQL Server Update table (data for another table is updated with data from a single table)