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Wikibase\EntityPerPageTable::getItemsWithoutSitelinks slow query with large LIMIT offset
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Description

This query form appears in the slow log for wikidatawiki on WMF S5:

SELECT /* Wikibase\EntityPerPageTable::getItemsWithoutSitelinks ? */ epp_entity_id AS entity_id FROM `wb_entity_per_page` LEFT JOIN `wb_items_per_site` ON ((ips_item_id = epp_entity_id)) WHERE (ips_site_page IS NULL) AND epp_entity_type = 'item' ORDER BY epp_page_id DESC LIMIT 1940000, 51;

Offset 1940000... wow! :-)

Can we cap the possible limit offset, or handle pagination differently?

Details

Reference
bz65333

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Event Timeline

bzimport raised the priority of this task from to Medium.Nov 22 2014, 3:11 AM
bzimport set Reference to bz65333.
bzimport added a subscriber: Unknown Object (MLST).
Lydia_Pintscher removed a subscriber: Unknown Object (MLST).
Lydia_Pintscher removed a subscriber: Unknown Object (MLST).
SELECT page_id, page_title FROM page_props INNER JOIN page ON page_id = pp_page WHERE pp_propname = 'wb-sitelinks' AND pp_sortkey = 0;
Addshore assigned this task to Ladsgroup.
Addshore added a subscriber: Addshore.

The entity per page table is gone (see T95685) so this task / issue can be resolved.