set ansi_nulls [on/off] 与 set quoted_identifier [on/off]

set ansi_nulls [on/off] 跟null等相关
set ansi_nulls off
可以使用=做比较 select * from a where price=null 若此时a中有price為NULL的就可以选出來
而在set ansi_nulls on时候
只能写 select * from a where price is null

set quoted_identifier [on/off] 跟标示符相关
set quoted_identifier on
“当 SET QUOTED_IDENTIFIER 为 ON 时，标识符可以由双引号分隔，而文字必须由单引号分隔。当 SET QUOTED_IDENTIFIER 为 OFF 时，标识符不可加引号，且必须遵守所有 Transact-SQL 标识符规则。”

SET QUOTED_IDENTIFIER ON
SELECT * FROM "USER" WHERE a='netasp'

SET QUOTED_IDENTIFIER ON
SELECT * FROM [USER] WHERE a='netasp'

SET QUOTED_IDENTIFIER OFF
SELECT * FROM [USER] WHERE a="netasp"

SET QUOTED_IDENTIFIER OFF
SELECT * FROM [USER] WHERE a= ' netasp'