Cosmin Prund <cprund@xxxxxxxxx> writes: > I know it's an odd choice of plan - that's why I'm here! Indeed. I cannot reproduce it here on 10.11: regression=# create table bb(f1 smallint, f2 serial, primary key(f1,f2)); CREATE TABLE regression=# explain select * from bb where f1 = 92 and f2 in (10,11); QUERY PLAN ----------------------------------------------------------------------- Index Only Scan using bb_pkey on bb (cost=0.15..8.34 rows=1 width=6) Index Cond: ((f1 = 92) AND (f2 = ANY ('{10,11}'::integer[]))) (2 rows) As I said before, as long as it chooses an indexscan at all, I wouldn't expect variation in what clauses it chooses to use with the index. So I don't see why this trivial example doesn't replicate your result. If you try exactly the above on your database, do you get my result, or a plan more like yours? I wonder if you have some extension installed that's causing the operators to be interpreted differently. BTW, why do you have two identical indexes on the table? > Indexes: > "PK_LucrareBugetDate" PRIMARY KEY, btree ("LucrareBugetVersiuneId", > "LucrareBugetDateId") > "IX_LucrareBugetDate_LucrareBugetVersiuneId_LucrareBugetDateId" btree > ("LucrareBugetVersiuneId", "LucrareBugetDateId") That shouldn't be affecting this either, but it seems wasteful. regards, tom lane