Option
copy of vector
How the copy of a vector column that the store keeps in memory holds its numbers.
Value
'small'. Left out, the copy keeps every number as it is stored, four bytes each, and a search is exact.
With 'small' the copy keeps one byte a number: about a quarter of the memory, 74 MB in place of 294 MB for 50,000 vectors of 1,536 numbers. A search then finds the best limit times four rows by the small copy, reads their full vectors from the table, and answers the nearest limit of those by the full vectors. That is not exact: on 50,000 vectors of 1,536 numbers the best ten agree with an exact search in nine of ten or more. Each row that such a near answers says so with exact: false beside its distance. It is for a column whose copy would not fit in memory otherwise; it is read when the store builds its copy, so a change of it holds from the next opening of the app.
Example
meaning: vector({ size: 1536, model: embedder, copy: 'small' })