Re: simplify query?

[Michael Conlen]

What you want to do is reduce the query. Logic is reduced using 
similar rules to algebra.

Think of or operations as addition and and operations as 
multiplication and you can manipulate them using the same rules as you 
do in algebra.

select * from t where (a and b) or (a and c);

where a, b and c are conditions

this query could be restated as

select * from t where a and (b or c);

your query is of the form

(a or b or c) and (d or e or f),

which I don't think can be reduced any further, but it can certainly be 
made more complicated as in (a and d) or (a and e) or (a and f) or (b 
and d) ...

--
Michael Conlen
Reto Baudenbacher wrote:

hi

Sorry for this newbie-question: 

is it possible to simplifiy the following (working) query?



SELECT * FROM mytable WHERE 

((col1 LIKE '%test%') OR (col2 LIKE '%test%') OR (col3 LIKE 'test%')) 

AND

(col5 = 'y' OR col6 = 'y' OR col7 = 'y') ORDER BY col1



Thanks for any suggestions!
Reto Baudenbacher
 



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simplify query?

[Reto Baudenbacher]

hi

Sorry for this newbie-question: 

is it possible to simplifiy the following (working) query?



SELECT * FROM mytable WHERE 

((col1 LIKE '%test%') OR (col2 LIKE '%test%') OR (col3 LIKE 'test%')) 

AND

(col5 = 'y' OR col6 = 'y' OR col7 = 'y') ORDER BY col1




Thanks for any suggestions!
Reto Baudenbacher


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Re: simplify query?

[Egor Egorov]

Reto Baudenbacher [EMAIL PROTECTED] wrote:
 hi
 
 Sorry for this newbie-question: 
 
 is it possible to simplifiy the following (working) query?
 
 
 
 SELECT * FROM mytable WHERE 
 
 ((col1 LIKE '%test%') OR (col2 LIKE '%test%') OR (col3 LIKE 'test%')) 
 
 AND
 
 (col5 = 'y' OR col6 = 'y' OR col7 = 'y') ORDER BY col1

What do you mean 'simplifiy'? You can rewrite the above query using UNION instead of 
OR, but the new query will not be very simple, too.



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