Delimited Identifiers

When the quoted_identifier option is set to on, you do not need to use double quotes around an identifier if the syntax of the statement requires that a quoted string contain an identifier.

For example:
set quoted_identifier on
create table "1one" (c1 int)
However, object_id requires a string, so you must include the table name in quotes to select the information:
select object_id ('1one')
-----------------------
  896003192
You can include an embedded double quote in a quoted identifier by doubling the quote:
create table "embedded""quote" (c1 int)
However, there is no need to double the quote when the statement syntax requires the object name to be expressed as a string:
select object_id ('embedded"quote')