TL;DR.
I think there is a I think there is a problem with your created_in column from the customer_entity table in one of the environments. For some reason the size of the column is not taken into consideration.
May be the mysql version but this is just a speculation.
[EDIT]
The above assumption was wrong.
The problem with yourappears because the attribute created_in column from theis marked as customer_entityis_filterable_in_grid = 1 tableand is_searchable_in_grid = 0 in one of the environments. For some reason the size of the column is not taken into considerationcustomer_eav_attribute table.
MayMake is_searchable_in_grid = 1 (as it should be the mysql version but this is just a speculationby default) and everything should be OK.
Make it
[/EDIT]
This is bugging me so I decided to invest a bit in it.
I debugged the createFlatTable method mentioned above and I see that for the created_in attribute comes up with type searchable even if in the indexer.xml it appears as filterable. I don't know yet why that happens. will post back when I find out why.
[Second degree edit]
Continuing the idea from the edit above, the type of the flat column filterable or searchable is determined for the customer attributes by the method Magento\Customer\Model\Indexer\AttributeProvider::getType.
protected function getType(Attribute $attribute)
{
if ($attribute->canBeSearchableInGrid()) {
$type = 'searchable';
} elseif ($attribute->canBeFilterableInGrid()) {
$type = 'filterable';
} else {
$type = 'virtual';
}
return $type;
}
In your case, you get the attribute type filterable and because this is a text attribute mysql cannot create the index on it.
Make sure your attribute is marked as is_searchable_in_grid and it will get the type searchable when the flat table is built and no index will be added to it.
