[OAK-6897] XPath query: option to _not_ convert "or" to "union"

• Type: Improvement
• Status: Open
• Priority: Trivial
• Resolution: Unresolved
• Component/s: query
• Assignee: Thomas Mueller
• Reporter: Thomas Mueller
• Created: 02/Nov/17 11:39
• Updated: 19/Nov/19 14:34

Description

Right now, all XPath queries that contain "or" of the form "@a=1 or @b=2" are converted to SQL-2 "union". In some cases, this is a problem, specially in combination with "order by @jcr:score desc".

Now that SQL-2 "or" conditions can be converted to union (depending if union has a lower cost), it is no longer strictly needed to do the union conversion in the XPath conversion. Or at least emit different SQL-2 queries and take the one with the lowest cost.