ahmed24
msg:4530137 | 10:02 am on Dec 21, 2012 (gmt 0) |
I think i've figured it out. i combined the two with a OR in between them and it seems to be working. Is this the correct way?
My syntax now looks like this:
MINUTES IS NOT NULL AND MINUTES='60' OR MINUTES IS NOT NULL AND MINUTES='30' AND DESCRIPTION NOT LIKE '%Test%'
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bhonda
msg:4530146 | 12:23 pm on Dec 21, 2012 (gmt 0) |
Be careful with mixing AND and OR in the same statement without using brackets.
I would assume you want something like -
(MINUTES IS NOT NULL AND MINUTES='60')
OR
(MINUTES IS NOT NULL AND MINUTES='30' AND DESCRIPTION NOT LIKE '%Test%')
Because this is different and will return completely different results -
(MINUTES IS NOT NULL AND MINUTES='60' OR MINUTES IS NOT NULL)
AND
MINUTES='30' AND DESCRIPTION NOT LIKE '%Test%'
Using a mix of AND and OR in the same statement relies on them being interpreted in a specific order, and it's never clear just by looking at the statement how it's going to work.
It's like in maths, what is the result of -
3 + 5 * 2?
Depending on the order in which you make the calculations, the result is either 16 or 13.
Whereas using brackets, you can ask -
3 + (5 * 2)
or
(3 + 5) * 2
Likewise, make sure you always explicitly define what is being compared with AND and what is being compared with OR.
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ahmed24
msg:4531117 | 12:39 pm on Dec 26, 2012 (gmt 0) |
Thanks for your reply.
My original single statement is already within brackets because there is AND statements before and after it like this:
AND (MINUTES IS NOT NULL AND MINUTES='60' ) AND
so, to combine both, will it need to be like this:
AND ((MINUTES IS NOT NULL AND MINUTES='60') OR (MINUTES IS NOT NULL AND MINUTES='30' AND DESCRIPTION NOT LIKE '%Test%') ) AND
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physics
msg:4531225 | 10:43 pm on Dec 26, 2012 (gmt 0) |
Do you really need MINUTES IS NOT NULL when you're also specifying an amount for minutes? Seems unnecessary and confusing - unless for some reason you're finding that you need it I'd get rid of it. In that case this would be a simpler version of your query:
AND ( MINUTES='60' OR ( MINUTES='30' AND DESCRIPTION NOT LIKE '%Test%' ) )
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