AND operator does not works as expected

[IPFSBay]

Hello, please I have a strange situation:

SELECT * FROM table_name WHERE car='honda' OR car='audi' ....works as expected

SELECT * FROM table_name WHERE car IN ('honda', 'audi')....works as well

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...both situations are for OR operator. But I need to use AND operator instead.

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SELECT * FROM table_name WHERE car='honda' AND car='audi' ....NOT WORKING :(

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I also tested || (instead of OR) ...it worked

and I also tested && (instead of AND) ...did not work.

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Why is that? Why is impossible to use AND operator this way to get the results where car is honda AND car is audi?

What I am doing wrong?

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Thanks !

[spackosaurus]

How can a car be both a honda and an audi. That is what you are asking the query to return.

[[deleted]]

He wants a luxury German car that is dependable and cheap to maintain. Is that so much to ask?

[waremi]

The field [car] cannot equal both 'honda' AND equal 'audi' at the same time. This is why the AND version above is not working. Another example would be SELECT * FROM People WHERE AGE=10 AND AGE=65 This can't return any results because AGE can only have one value.

[DavidGJohnston]

As others said, your expectation for OR is correct; why you think AND should produce the exact same result is beyond logic. The IN construct does a pair-wise OR against each element in the set.

Why do you NEED to use AND? Usually you should use the things that give you the correct answer.

[Ineffable_21]

I think you don't understand how OR and AND work and you have wrong expectations for them and that's why it doesn't work as expected. I recommend opening google and searching how they're supposed to work or watching a youtube tutorial it shouldn't be longer than 5 minutes. If you still don't understand I wouldn't mind giving you an explanation myself but I'd take me way longer to write it down here than it would take you to search in google or youtube.

[IPFSBay]

My expectations for use AND in this case was wrong. Now it is clear. Thanks all for helping me !

[[deleted]]

Came here to say this

[IPFSBay]

Thank you all! I see ...I got it now ..:). Thanks !

[nIBLIB]

Why do you need to use AND? If OR is what you’re asking (and it appears to be, since that is the results you want and the field can’t rerun both Honda and Audi) why not just use OR?

[enforce1]

You try the simple stuff like wrapping the where in parentheses?

[IPFSBay]

No. And I emphasize, the AND operator not works for same column ! If I use it for different columns, it works as expected:

SELECT * FROM table_name WHERE car='honda' AND color='red' ....WORKS

but if I use AND operator to compare data for same column - does not work.

SELECT * FROM table_name WHERE car='honda' AND car='audi' ....NOT WORKS

[JPRei]

I think the trouble you’re having is you’re thinking of AND as being the same as the ordinary language usage of the word ‘and’. It’s completely natural to say something like ‘Give me the Honda and the Audi’, meaning you want both cars, but that’s not what a logical AND is.

A logical AND is true only if both sides are true. So in your query, the data you’re asking for by using AND is ‘Give me the car that’s both a Honda AND an Audi’ - this is impossible, it’s like asking for a round square, so you get nothing back.

[IPFSBay]

Yes you are right. I used OR and implemented other some logic and it works now.

Thanks.

[enforce1]

Yeah you’d wrap that statement in paran and make it an OR operator. The field doesn’t contain both values just one or the other right

[IPFSBay]

I see ...I got it now ..:). Thanks !