Reinstalled my laptop and upgraded to KDE Plasma 6. After a while, I noticed that mail search in KMail no longer works. Reading Akonadi logs revealed this gem. I’m no Akonadi expert, but creating an SQL statement with 40k variables does not seem wise to me. Guess how many mails I have in my inbox?

org.kde.pim.akonadiserver: Handler exception when handling command FetchItems on 
connection  akonadi_indexing_agent (0x56536e3d9e50) : Failed to query database
org.kde.pim.akonadi_indexer_agent: Failed to fetch items:  "Failed to query database"
org.kde.pim.akonadi_indexer_agent: Indexing failed:  ""
org.kde.pim.akonadiserver: DATABASE ERROR while PREPARING QUERY:
org.kde.pim.akonadiserver:   Error code: "1"
org.kde.pim.akonadiserver:   DB error:  "too many SQL variables"
org.kde.pim.akonadiserver:   Error text: "too many SQL variables Unable to execute statement"
org.kde.pim.akonadiserver:   Query: "SELECT DISTINCT ResourceTable.name FROM
PimItemTable  LEFT JOIN CollectionTable ON ( PimItemTable.collectionId = CollectionTable.id )
 LEFT JOIN ResourceTable ON ( CollectionTable.resourceId = ResourceTable.id ) WHERE (
PimItemTable.id IN ( :0, :1, :2, :3, :4, :5, :6, :7, :8, :9, :10, :11, :12, :13,
 :14, :15, :16, :17, :18,  :19, :20, :21, :22, :23, :24, :25, :26, :27, :28, 
:29, :30, :31, :32, :33, :34, :35, :36, :37, :38, :39, :40, :41, :42, :43, 
:44, :45, :46, :47, :48, :49, :50, :51, :52, :53, :54, :55, :56, :57, :58,
:59, :60, :61, :62, :63, :64, :65, :66, :67, :68, :69, :70, :71, :72,
...
...MANY...MORE...
...
:44273, :44274, :44275, :44276, :44277, :44278, :44279, :44280, :44281, :44282, :44283, 
:44284, :44285, :44286, :44287, :44288, :44289, :44290, :44291, :44292, :44293, :44294, 
:44295, :44296, :44297, :44298, :44299, :44300 ) )"
org.kde.pim.akonadiserver: Handler exception when handling command FetchItems on
 connection akonadi_indexing_agent (0x56536e3d9e50) : Failed to query database
org.kde.pim.akonadi_indexer_agent: Failed to fetch items:  "Failed to query database"

Having reasonably large mailboxes is no longer a thing, is it? 😞

Edit: Broke lines.