CREATE TABLE IF NOT EXISTS /*_*/wbc_entity_usage (
  eu_row_id         BIGINT NOT NULL PRIMARY KEY AUTO_INCREMENT,
  eu_entity_id      VARBINARY(255) NOT NULL, -- the ID of the entity being used
  eu_aspect         VARBINARY(37) NOT NULL,  -- the aspect of the entity. See EntityUsage::XXX_USAGE for possible values.
  eu_page_id        INT NOT NULL,            -- the ID of the page that uses the entities.
  eu_touched        BINARY(14) NOT NULL DEFAULT '' -- timestamp corresponding to page.page_touched
) /*$wgDBTableOptions*/;

-- record one usage per page per aspect of an entity
CREATE UNIQUE INDEX /*i*/eu_entity_id ON /*_*/wbc_entity_usage ( eu_entity_id, eu_aspect, eu_page_id );

-- look up (and especially, delete) usage entries by page id
CREATE INDEX /*i*/eu_page_id ON /*_*/wbc_entity_usage ( eu_page_id, eu_entity_id ) ;
