How do xiangqi databases let you search games by position?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
By converting a position into its FEN-style string and matching it against positions stored inside recorded games, rather than searching the move text itself. This is the same underlying technique chess database software uses, adapted for xiangqi's ten-rank board and extra piece letters.
Why position search needs more than move text
Two completely different move sequences can transpose into an identical position, so searching only the written moves would miss games that reached the same point by a different route. Indexing by position instead catches every game that passed through it, regardless of the path taken to get there.
What this is useful for
Finding every recorded example of a specific opening structure, a particular endgame configuration, or a tactical pattern you want to study, without having to already know which named opening or specific move order to search for.
Related questions
Does this site use position-based verification the same way?
Yes, every board on this site is defined by a FEN-style string and checked through the rules engine; see what FEN is in xiangqi.
Can you search by a partial position, like just the palace area?
Some tools support partial or pattern-based matching, though full-position search is the more common and reliable baseline.
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