ZF-4364: Using SkipData info to improve search performance
Each term within an index has a list of matched documents. This list may be large enough and it may take a long time to load it.
This list also has some additional subindex known as "skip data". This info allows to check directly if some document matches specified term.
Zend_Search_Lucene should use skipData to optimize search performance.
That may be done by reordering of subsearches execution.