The from Clause

Use the from clause to specify the tables and views to use in a join statement. .

This is the clause that indicates to SAP ASE that a join is desired. You can list the tables or views in any order. The order of tables affects the results that appear only when you use select * to specify the select list.

At most, a query can reference 250 tables and 46 worktables (such as those created by aggregate functions). The 250-table limit includes:
The following example joins columns from the titles and publishers tables, doubling the price of all books published in California:
begin tran
update titles 
  set price = price * 2 
  from titles, publishers 
  where titles.pub_id = publishers.pub_id 
  and publishers.state = "CA"
rollback tran
Table or view names can be qualified by the names of the owner and database, and can be given correlation names for convenience. For example:
select au_lname, au_fname 
where = 
Related concepts
Join More Than Two Tables
Views: Limit Access to Data