update syntax

A simplified version of the update syntax for updating specified rows with an expression is:

update table_name 
     set column_name = expression 
     where search_conditions

For example, if Reginald Blotchet-Halls decides to change his name, here is how to change his row in the authors table:

update authors 
set au_lname = "Health", au_fname = "Goodbody" 
where au_lname = "Blotchet-Halls"

This statement updates a table based on data from another table:

update table_name 
     set column_name = expression 
          from table_name 
          where search_conditions

You can set variables in an update statement with:

update table_name 
     set variable_name = expression 
          where search_conditions

The full syntax for update is:

update [[database.]owner.]{table_name | view_name}
     set [[[database.]owner.]{table_name. | view_name.}] 
          column_name1 = 
          {expression1 | null | (select_statement)} |
          variable_name1 = 
          {expression1 | null | (select_statement)} 
          [, column_name2 = {expression2 | null |
          (select_statement)}]... | 
               variable_name2 = {expression1 | null |                  (select_statement)} 
     [from [[database.]owner.] {table_name | view_name} 
          [, [[database.]owner.] {table_name | 
          view_name}]]... 
     [where search_conditions]