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NULLIF - Revision history
2013-05-18T18:42:15Z
Revision history for this page on the wiki
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Peter at 11:28, 28 October 2012
2012-10-28T11:28:28Z
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<td colspan='2' style="background-color: white; color:black;">Revision as of 11:28, 28 October 2012</td>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><h1>NULLIF</h1></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><h1>NULLIF</h1></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><p>NULLIF returns NULL if the two arguments are equal; otherwise NULLIF returns the first argument. </p></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><p>NULLIF returns NULL if the two arguments are equal; otherwise NULLIF returns the first argument. </p></div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>   <li>[[COALESCE |COALESCE function]]</li></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>   <li>[[COALESCE |COALESCE function]]</li></div></td></tr>
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Peter
http://sqlzoo.net/w/index.php?title=NULLIF&diff=1326&oldid=prev
Connor: Created page with "<table align='right' border='1'> <caption>Compatibility</caption> <tr><th colspan='3'>NULLIF(f1,f2)</th></tr> <tr><td align='center'>'''Engine'''</td><td align='center'>'''OK'..."
2012-07-16T13:34:22Z
<p>Created page with "<table align='right' border='1'> <caption>Compatibility</caption> <tr><th colspan='3'>NULLIF(f1,f2)</th></tr> <tr><td align='center'>'''Engine'''</td><td align='center'>'''OK'..."</p>
<p><b>New page</b></p><div><table align='right' border='1'><br />
<caption>Compatibility</caption><br />
<tr><th colspan='3'>NULLIF(f1,f2)</th></tr><br />
<tr><td align='center'>'''Engine'''</td><td align='center'>'''OK'''</td><td align='center'>'''Alternative'''</td></tr><br />
<tr><td align='left'>ingres</td><td>Yes</td><td></td></tr><br />
<tr><td align='left'>mysql</td><td>Yes</td><td></td></tr><br />
<tr><td align='left'>oracle</td><td>Yes</td><td></td></tr><br />
<tr><td align='left'>postgres</td><td>Yes</td><td></td></tr><br />
<tr><td align='left'>sqlserver</td><td>Yes</td><td></td></tr><br />
</table><br />
<h1>NULLIF</h1><br />
<p>NULLIF returns NULL if the two arguments are equal; otherwise NULLIF returns the first argument. </p><br />
<p></p> <br />
<pre style='width:60ex'><br />
NULLIF(x,y) = NULL if x=y<br />
NULLIF(x,y) = x if x != y <br />
</pre><br />
<br />
<div class='ht'><br />
NULLIF can be used to replace a specific value with NULL. In this example the party Lab is replaced with NULL.<br />
<source lang='sql' class='def e-oracle'><br />
SELECT name, party<br />
,NULLIF(party,'Lab') AS aff<br />
FROM gisq.msp WHERE name LIKE 'C%'<br />
</source><br />
<source lang='sql' class='def'><br />
SELECT name, party<br />
,NULLIF(party,'Lab') AS aff<br />
FROM msp WHERE name LIKE 'C%'<br />
</source><br />
</div><br />
<br />
<p>See also</p><br />
<ul><br />
<li>[[COALESCE |COALESCE function]]</li><br />
</ul></div>
Connor