subquery not_in returns NULL

[hrasguido]

Issue

When I use "not_in" the sql result is NULL. But if I use only "in", the result works fine

Reproduction

table1.joins(:table2)
.where.has{  id.in table3.select(:table1_id).where(table3_id: 162)    }

Result

SELECT "table1".* FROM "table1" INNER JOIN "table2" ON "table2"."table1_id" = "table1"."id"
WHERE  "table1"."id" IN (SELECT "table3"."table1_id" FROM "table3" WHERE  "table3"."table3_id" = 162)

But when I use not_in

table1.joins(:table2)
.where.has{  id.not_in table3.select(:table1_id).where(table3_id: 162)    }

Result

SELECT "table1".* FROM "table1" INNER JOIN "table2" ON "table2"."table1_id" = "table1"."id"
WHERE "table1"."id" NOT IN (NULL)

[rzane]

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