sql server判斷是否為null

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sql server

　　替換null:isnull(arg,value)

　　如:select isnull(price,0.0) from orders ,如果price為null的話，用0.0替換

　　與null比較: is not null，is null

　　如 select * from orders where price is null ,price等於null

　　如: select * from orders where price is not null ,price不等於null

　　Oracle

　　替換null: nvl(arg,value)

　　如: select nvl(price,0.0) form orders

　　與null比較: is not null，is null

　　如 select * from orders where price is null ,price等於null

　　如: select * from orders where price is not null ,price不等於null

sql server判斷是否為null