[SOLVED] plus/minus a value

[_spaz]

Is it possible to query a result and search plus/minus the value?

 

example:

say my value is "10"

how do I get it to include results +/- 5

so that I get "5 6 7 8 9 10 11 12 13 14 15"

 

Not sure if its possible and I can't find my answer anywhere.....

 

thx.

 

[PFMaBiSmAd]

Take the absolute value of the difference between the desired value (10 in your example) and the value in the table. Then return those rows with a result that is less-than or equal to 5.

[PFMaBiSmAd]

Query to accomplish the above statement -

 

$query = "SELECT your_column, ABS(10-your_column) as dif FROM your_table HAVING dif <= 5";

[corbin]

If you did the processing in PHP, you could have it such that indexes were still usable:

 

 

SELECT * FROM blah WHERE field BETWEEN 5 AND 15;

 

Edit: Hrmmm....  Or maybe I misunderstood something....

[artacus]

PFM's approach will cause a full table scan. Which will be an issue if you've got a large table.

 

Corbin's approach will perform better, but you don't necessarily need to preprocess in php.

 

BETWEEN ($id - 5) AND ($id + 5)

[_spaz]

Thanks guys this issue is now resolved with your help.