Content Comparison

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SELECT * FROM fragment WHERE anchor_id = ? AND xpath IN (?,?,?,?,?,?...,?)
SELECT * FROM fragment WHERE anchor_id = ? AND xpath IN (?,?,?,?,?,?...,?)
SELECT * FROM fragment WHERE anchor_id = ? AND xpath IN (?,?,?,?)

Observations

Disadvantage:

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Lists.partition only supports Lists

If a public method takes in a Collection (and not a List), then either an ArrayList copy of the Collection is needed, or the public API method needs to be changes to List, as Lists.partition requires a List to partition.

To Do: measure performance impact of this, if any.

Batching on repository methods versus API methods

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It is unclear if this has better performance in practice (limited testing shows both solutions have similar performance, but the test scenarios may be unrealistic).

Observations

Disadvantage: extra dependency

Extra dependencies could add possible risks of dependency issues, security issues, etc. in future.

Disadvantage of arrays: Limited array type support

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void deleteByAnchorIndeleteByAnchorIdIn(int[] anchorIds);

Advantage of arrays: Code already using Postgres arrays can

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be simplified

The current FragmentRepository has code already using Postgres arrays to support "LIKE ANY" logic (using LIKE with a collection). However, it currently uses query parameters, and is thus limited to 32K parameters.

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