In SQL syntax, is 'from' in 'delete from' optional if you plan to use 'where'?

Question

I am new to SQL. We have some code that should work on SQL Server 2005/2008, Oracle 10 as well as Sybase.

I was writing a script to try to figure out which tables a

Answer 1

At this place the FROM is optional (SQL Server, Oracle, Sybase).

However, there are subtle differences: Oracle for instance allows assigning an alias to the table name, where SQL Server doesn't; and other things are also a little bit different.

Also note that your FROM sample is differnet from the following where it is mandatory:

DELETE phone_book FROM some_table WHERE ...