sql判定null Oracle,sql server

oracle


那么,有未有啥样方法让sql
server的这些暗中认可机制与oracle相近啊?答案是:未有

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

奥门永利402com,在sql
server中则刚刚相反,null值会被感到是一个Infiniti小的值,所以若是遵照升序排列的话,则会被排在最前头

1.替换null: nvl(arg,value)

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

如:select * from orders where price is null               price等于null

select [id]

sql server

则会看出如下的效果

如:select isnull(price,0.0) from orders

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

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

那样的话,就足以看到如下的效应

如 select * from orders where price is null                 
price等于null

与null比较: is not null,is null

2.与null比较: is not null,is null

oracle

如: select nvl(price,0.0) form orders

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

2.与null比较: is not null,is null

如: select nvl(price,0.0) form orders

oracle

替换null:isnull(arg,value)

1.替换null:isnull(arg,value)

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