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SELECT DATE_FORMAT(MAX(timestamp)<wbr />,'%M %e, %Y') AS lastupdated FROM<br />
(SELECT MAX(timestamp) as timestamp FROM table1 <br />
UNION SELECT MAX(timestamp) AS timestamp FROM table2<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table3<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table4)<br />
You may find that this is pretty inefficient for lots of rows. &nbsp;Another approach is to have a lastupdated table that contains one row called timestamp and whenever you get an insert, you update that row to the latest timestamp. &nbsp;This adds to the time of your insert, but unnoticeably, and would reduce this query to:<br />
SELECT DATE_FORMAT(timestamp, '%M %e, %Y') AS lastupdated FROM lastupdated<br />

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thanks for this, I'm getting this error:<br />
&quot;Every derived table must have its own alias&quot;<br />
<br />
<br />
I now have this..<br />
$query_update = &quot;SELECT DATE_FORMAT(MAX(timestamp)<wbr />,'%M %e, %Y') AS lastupdated FROM <br />
(SELECT MAX(timestamp) as timestamp FROM table1<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table2<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table3<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table4<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table5<br />
UNION SELECT MAX(timestamp) AS timestamp FROM table6)<br />
&quot;;<br />

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that's great, seems to be working spot on..thanks
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<div class="content wysiwyg-content">
I have a &quot;site last updated&quot; in the foot of the page, I managed to use the following to do this with one table:<br />
<br />
$query_update = &quot;SELECT DATE_FORMAT(MAX(timestamp)<wbr />,'%M %e, %Y') AS lastupdated FROM news&quot;;<br />
<br />
<br />
Now I have more tables to add and need a way to do something like this if possible:<br />
<br />
$query_update = &quot;SELECT DATE_FORMAT(MAX(table1.tim<wbr />estamp,tab<wbr />le2.timest<wbr />amp,table3<wbr />.timestamp<wbr />, table4.timestamp),'%M %e, %Y') AS lastupdated FROM table1,table2,table3,table<wbr />4&quot;;<br />
<br />
thanks
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I have a "site last updated" in the foot of the page, I managed to use the following to do this with one table:

$query_update = "SELECT DATE_FORMAT(MAX(timestamp),'%M %e, %Y') AS lastupdated FROM news";


Now I have more tables to add and need a way to do something like this if possible:

$query_update = "SELECT DATE_FORMAT(MAX(table1.timestamp,table2.timestamp,table3.timestamp, table4.timestamp),'%M %e, %Y') AS lastupdated FROM table1,table2,table3,table4";

thanks

max timestamp from several tables with timestamp column

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