t = db.stages_and_hashed; t.drop(); var collname = "stages_and_hashed"; var N = 50; for (var i = 0; i < N; ++i) { t.insert({foo: i, bar: N - i, baz: i}); } t.ensureIndex({foo: 1}); t.ensureIndex({bar: 1}); t.ensureIndex({baz: 1}); // Scan foo <= 20 ixscan1 = { ixscan: { args: { name: "stages_and_hashed", keyPattern: {foo: 1}, startKey: {"": 20}, endKey: {}, startKeyInclusive: true, endKeyInclusive: true, direction: -1 } } }; // Scan bar >= 40 ixscan2 = { ixscan: { args: { name: "stages_and_hashed", keyPattern: {bar: 1}, startKey: {"": 40}, endKey: {}, startKeyInclusive: true, endKeyInclusive: true, direction: 1 } } }; // bar = 50 - foo // Intersection is (foo=0 bar=50, foo=1 bar=49, ..., foo=10 bar=40) andix1ix2 = { andHash: {args: {nodes: [ixscan1, ixscan2]}} }; res = db.runCommand({stageDebug: {plan: andix1ix2, collection: collname}}); assert.eq(res.ok, 1); assert.eq(res.results.length, 11); // Filter predicates from 2 indices. Tests that we union the idx info. andix1ix2filter = { fetch: { filter: {bar: {$in: [45, 46, 48]}, foo: {$in: [4, 5, 6]}}, args: {node: {andHash: {args: {nodes: [ixscan1, ixscan2]}}}} } }; res = db.runCommand({stageDebug: {collection: collname, plan: andix1ix2filter}}); assert.eq(res.ok, 1); assert.eq(res.results.length, 2);