The bug to which the chart was not displayed occurred by WassUp 1.6.5.
It operated normally excluding the chart, but a chart is not displayed.
The version of MySQL of the hosting service that I am using seem to be and there be a cause in the thing that is MySQL 4.0.24.
This bug was solved by correcting SQL sentence.
I edited main.php as follows.
WassUp -> lib -> main.php
It looks for the following code.
$aitems = $wpdb->get_results("SELECT COUNT(DISTINCT WassUp_id) as items,
COUNT(WassUp_id) as pages,
DATE_FORMAT(FROM_UNIXTIME(CAST((timestamp-$UTCoffset) AS UNSIGNED)),
‘$x_axes_label’) as thedate FROM ".$this->tableName." WHERE timestamp BETWEEN $hour_fromdate AND $hour_todate ".$this->whereis." $ss GROUP BY
DATE_FORMAT(FROM_UNIXTIME(CAST((timestamp-$UTCoffset) AS UNSIGNED)),
‘$Ctimeformat’) ORDER BY timestamp", ARRAY_A);
Correct a part of the code as follows.
"timestamp-$UTCoffset" to "timestamp - $UTCoffset"
It is safe ..only putting space.. before and behind operator "-".
All bugs can not necessarily correspond by this method.
However, there seems to be a problem in an interchangeable version of this SQL sentence about the bug to which the chart is not displayed when I examine it.
As for the occurrence of a similar bug, it might be good to try rewriting this SQL sentence.
My server environment etc. are put on my blog.
Please see interesting one by all means.
I want to report on the bug to the forum of WassUp in a few days.