From MySQL 5.7 onwards, the error SQLSTATE: Syntax error or access violation: 1055 Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column will appear if any non aggregated columns are in the select list, which is not in the group by clause. This article discusses one such use case with Mautic and how we solved it.
Some of you might have seen this error message while trying to upgrade Mautic in your system: "[Symfony\Component\Debug\Exception\ClassNotFoundException] Attempted to load class "ZipArchive" from the global namespace. Did you forget a "use" statement?" while upgrading Mautic version.
To upgrade Mautic to the latest Mautic 4.0.0 version, We will need to first update the present Mautic version 3.3.3 to Mautic 3.3.4 version, which is the stable version before the Mautic 4.0.0 version. It is always recommended to upgrade the Mautic version through the command line. Let us see the commands to upgrade the Mautic version. From the document root of mautic, we will need to run the below command to check whether any version upgrade is pending.