UPDATE

UPDATE modifies zero to many rows in the database. Rows which meet the search_condition are modified based on the column_name = expression list. An UPDATE operation may not modify a nested or primary key.

UPDATE table_name SET equality_list WHERE search_condition 

   equality_list ::=
      column_name = expression {,column_name=expression...} 

   expression ::=
      term [operator {term|expression}] 

   term ::=
      [[account.]table_name.]column_name
      | constant 

   operator ::=
      + | - | * | / | string concatenation(||) 

   search_condition ::=
      [NOT] conditional_expression [{AND|OR} [NOT] conditional_expression...] 

   conditional_expression ::=
      expression comparison_operator {expression|USER}
      | expression comparison_operator {ALL|ANY|SOME} (select_statement)
      | expression [NOT] BETWEEN expression AND expression
      | expression [NOT] IN ({select_statement | value [, value...]})
      | expression [NOT] LIKE value [ESCAPE value]
      | column_name IS [NOT] NULL
      | EXISTS (select_statement)

Example

UPDATE cust SET name = "John P. Smith" WHERE id = 123