select_command

select_command 
      ::= 
      "select" [ "all" | "distinct" ] 
      ( "*" | ( displayed_column { "," displayed_column } ) ) 
      "from" ( selected_table { "," selected_table } ) 
      [ "where" condition ] 
      { connect_clause } 
      { group_clause } 
      { set_clause } 
      { order_clause } 
      { update_clause } 

This rule is called by

explain_command
query
set_clause
subquery
to_modify_data