PostgreSQL - jumlah maksimum parameter dalam klausa IN?

Menurut kode sumber yang ada di sini, mulai dari baris 850, PostgreSQL tidak secara eksplisit membatasi jumlah argumen.

Berikut ini adalah komentar kode dari baris 870:

/*
 * We try to generate a ScalarArrayOpExpr from IN/NOT IN, but this is only
 * possible if the inputs are all scalars (no RowExprs) and there is a
 * suitable array type available.  If not, we fall back to a boolean
 * condition tree with multiple copies of the lefthand expression.
 * Also, any IN-list items that contain Vars are handled as separate
 * boolean conditions, because that gives the planner more scope for
 * optimization on such clauses.
 *
 * First step: transform all the inputs, and detect whether any are
 * RowExprs or contain Vars.
 */