Is it possible to do multiple SQL select statements within one query? Both select statements would be on the same table

Question

This is probably due to my limited SQL knowledge, but I'm attempting to obtain data using a statement like this:

SELECT hostname 
FROM mytable 
WHERE hostname NOT LIKE '%obl%' 
    AND group NOT IN ('group1','group2','group3','group4','group5','group6','group7')
    AND osname LIKE '%Windows%' 
    AND hostname NOT LIKE 'nic%'

I realize that is probably a very bad statement, but it has worked so far. In the beginning I exclude entries where hostname isn't like "obl". I have another query like this:

SELECT hostname 
FROM mytable 
WHERE hostname LIKE '%obl%' 
    AND group IN ('group9','group0')

From what I understand, joins wouldn't be used in this case, since both queries are on the same table (although my knowledge of joins is very limited). I'm accessing this database via a webservice, and I'm not certain what kind of database it is.

Does anyone have any ideas of how I could get the values from both queries in one query?

Answer 1

You should use a UNION statement.

SELECT hostname FROM mytable  
WHERE hostname  
    NOT LIKE '%obl%' AND 
    group NOT IN ('group1','group2','group3','group4','group5','group6','group7')  
    AND osname LIKE '%Windows%' 
    AND hostname not LIKE 'nic%'

UNION

SELECT hostname FROM mytable 
WHERE hostname 
    LIKE '%obl%' 
    AND group in ('group9','group0')

That will do it, but I think you could rethink those where conditions. I'll give it a thought and edit if necessary.

EDIT: You can achieve what you are trying to with a single query, no need for the union.

SELECT hostname FROM mytable 
WHERE (
    hostname NOT LIKE '%obl%' 
    AND group NOT IN ('group1','group2','group3','group4','group5','group6','group7') 
    AND osname LIKE '%Windows%' 
    AND hostname NOT LIKE 'nic%'
)
OR (
    hostname LIKE '%obl%' 
    AND group IN ('group9','group0')
)