SQL查询返回两个日期之间的行

Question

I am using this query to get the rows between two dates but I don't get the rows from the database, it returns an empty set (in db I have rows for that day)

Query:

select email 
from users
where date_email_sent between '17-May-12' AND '17-May-12'

When I try the query below I am getting 17th row alone

Query:

select email
from users
where date_email_sent between '17-May-12' AND '18-May-12'

Can any one plz suggest me how to get 17th records alone if start date and end date as same.

Thanks in advance.

Answer 1

Does the date_email_sent have a datetime value? If the column value like 2012-05-17 09:30:00.000 has both date and time, then you may need to put the time together with your date value in the where clause,

eg

where date_email_sent between '17-May-12 00:00:00.000' AND '17-May-12 23:59:59.000'

or you can look at the date value only for the field

where DATEADD(dd, 0, DATEDIFF(dd, 0, date_email_sent )) between '17-May-12' AND '17-May-12'

SQL always consider as 12am if you put date only, so there will be a problem if you want to compare a date with datetime value

Answer 2

When you specify a date without a time portion, the time is automatically assumed as 12:00 am. So when you write

date_email_sent between '17-May-12' AND '17-May-12'

This is effectively the same as

date_email_sent between '17-May-12 12:00AM' AND '17-May-12 12:00AM'

So as you can see, the two times are identical and naturally there are no records in the specified interval.

If you want all the records on one day, you need to measure from midnight until midnight the next day:

date_email_sent >= '17-May-12 12:00AM' and date_email_sent < '18-May-12 12:00AM'

or just:

date_email_sent >= '17-May-12' and date_email_sent < '18-May-12'

Alternatively, you can extract the day portion of the date and check that for the correct value. The specific date handling functions vary depending on your dbms.

Answer 3

In SQL Server you should do it like this.

select email 
from users
where date_email_sent >= '20120517' and 
      date_email_sent < dateadd(day, 1, '20120517')

If you use something else you have to replace dateadd with something else.

Answer 4

select email 
from users
where date_email_sent >= '17-May-12' AND date_email_sent < '18-May-12'

Answer 5

when you write BETWEEN '17-May-12' AND '17-May-12' so you haven't mentioned the time so in Date datatype it considered as

'17-May-12 00:00:00' AND '17-May-12 00:00:00'

so your range is limited that's why you didn't get records. you should mention time also to get the record with same date . In oracle you can write like this

BETWEEN to_date('dd-mm-yyyy hh24:mi','17-05-12 00:00') AND to_date('dd-mm-yyyy hh24:mi','17-05-12 23:59')