Difference between revisions of "ABS"

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<h3>ABS</h3>
 
<table>
 
<p>ABS returns the absolute value. The output is positive even if the input is negative:</p>
 
 
<table align='right' border='1'>
 
<table align='right' border='1'>
 
<caption>Compatibility</caption>
 
<caption>Compatibility</caption>
<caption>ABS(f)</caption>
+
<tr><th colspan='3'>ABS(f)</th></tr>
<tr><th>Engine</th><th>OK</th><th>Alternative</th></tr>
+
<tr><td align='center'>'''Engine'''</td><td align='center'>'''OK'''</td><td align='center'>'''Alternative'''</td></tr>
 
<tr><td align='left'>ingres</td><td>Yes</td><td></td></tr>
 
<tr><td align='left'>ingres</td><td>Yes</td><td></td></tr>
 
<tr><td align='left'>mysql</td><td>Yes</td><td></td></tr>
 
<tr><td align='left'>mysql</td><td>Yes</td><td></td></tr>
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<tr><td align='left'>sqlserver</td><td>Yes</td><td></td></tr>
 
<tr><td align='left'>sqlserver</td><td>Yes</td><td></td></tr>
 
</table>
 
</table>
<table class='Noborder'>
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<h1>ABS</h1>
<tr><th></th></tr>
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<p>ABS returns the absolute value. The output is positive even if the input is negative:</p>
<tr><td>ABS(x) = x if x>=0</td></tr>
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<pre style='width:40ex'>ABS(x) = x if x>=0
<tr><td>ABS(x) = -x if x<0</td></tr>
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ABS(x) = -x if x<0</pre>
</table>
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<div class='qu'>
 
<div class='qu'>
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The value 70000 is the target value, 500 is the "tolerance" so the test ABS(area-70000)<500 tests that the area is between 70000-500 and 70000+500. That is 69500<area<70500  
 
The value 70000 is the target value, 500 is the "tolerance" so the test ABS(area-70000)<500 tests that the area is between 70000-500 and 70000+500. That is 69500<area<70500  
 
<source lang='sql' class='def'>
 
<source lang='sql' class='def'>
SELECT name, area FROM bbc
 
WHERE ABS(area-70000)<500
 
</source>
 
 
<source lang='sql' class='ans'>
 
 
SELECT name, area FROM bbc
 
SELECT name, area FROM bbc
 
  WHERE ABS(area-70000)<500
 
  WHERE ABS(area-70000)<500
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</div>
 
</div>
  
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<p>See also</p>
 
<ul>
 
<ul>
   <li>[[CASE statement]]</li>
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   <li>[[CASE |CASE statement]]</li>
 
</ul>
 
</ul>
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 +
{{Languages}}

Latest revision as of 12:35, 6 September 2012

Compatibility
ABS(f)
EngineOKAlternative
ingresYes
mysqlYes
oracleYes
postgresYes
sqlserverYes

ABS

ABS returns the absolute value. The output is positive even if the input is negative:

ABS(x) = x if x>=0
 ABS(x) = -x if x<0

ABS can be useful for testing values that are "close". For example this query shows each country that has area that is roughly 70 thousand. The value 70000 is the target value, 500 is the "tolerance" so the test ABS(area-70000)<500 tests that the area is between 70000-500 and 70000+500. That is 69500<area<70500

SELECT name, area FROM bbc
 WHERE ABS(area-70000)<500

See also

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