How many rows are returned by these two select statements?

Discussion in 'Programming' started by Jagbani, Nov 3, 2010.

0
  1. #1
    2 and 2
    Each select statement actually returns 2 rows. You can use this script to check this:
    create table mytable
    ( id int identity(1,1)
    , mychar varchar(20)
    )
    go
    insert mytable select null
    insert mytable select ''
    insert mytable select ' '
    go
    set ansi_nulls on
    set ansi_null_dflt_on on
    select * from mytable
    where mychar is not null
    select * from mytable
    where mychar <> '' and mychar is not null
    select * from mytable
    where mychar <> ' ' and mychar is not null
    select * from mytable where mychar = ''
    select * from mytable where mychar = ' '
    set ansi_null_dflt_on off
    set ansi_nulls off
    go
    drop table mytable
     
    Jagbani, Nov 3, 2010 IP