geervani (9/24/2009)
The answer for the question is YES. FROM clause can be used in UPDATE query. But the example query given is wrong.something like this will work
update table1
set coulmn=a2.column
from table1 as a1, table2 as a2
where a1.colum1 = a2.column2
Agree.
Alternatively you can also use
update table1
set somecolumn=a2.column
from table2 as a2
where column1 = a2.column2
point here is if you dont specify alias for table to be updated in the from clause you can use it as table name reference. However, if you do specify alias for table1 in table from clause then you must reference the table with alias.
geervani: In your statement just to keep t-sql cleaner I would use following
update a1
set a1.somecolumn=a2.column
from table1 as a1, table2 as a2
where a1.column1 = a2.column2
Bhavesh
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