Info

We have come across a problem that was introduced with this change: SERVER-34012. The exact line causing this is https://github.com/mongodb/mongo/blame/master/src/mongo/db/matcher/expression_tree.cpp#L250. This problem can only be seen on MongoDB v5, earlier versions work properly. Steps to reproduce: Create "some" collection and then run: db.getCollection("some").aggregate({$match: { "$or" : [ { "x" : "a" }, { "x" : "b" }, { "x" : /c/ }] } }) Expected output: No failure. Output: uncaught exception: Error: command failed: { "ok" : 0, "errmsg" : "Failed to optimize pipeline :: caused by :: Failed to optimize expression :: caused by :: Incorrect number of non-equivalent expressions", "code" : 3401204, "codeName" : "Location3401204" } with original command request: { "aggregate" : "FileNodeVersions", "pipeline" : [ { "$match" : { "$or" : [ { "x" : "a" }, { "x" : "b" }, { "x" : /c/ } ] } } ], "cursor" : { }, "lsid" : { "id" : UUID("af1c7696-912f-4ad8-a53b-8eb9db5c0162") }

Top User Comments

xgen-internal-githook commented on Thu, 2 Jun 2022 13:30:42 +0000: Author: {'name': 'Timour Katchaounov', 'email': 'timour.katchaounov@mongodb.com', 'username': 'timourk'} Message: SERVER-66379 $or to $in conversion flawed (cherry picked from commit 951197b3834d509d7903efa4a66c0e9f79235262) (cherry picked from commit b499c915d1c21f063548c96d5d547dcfcda55754) Branch: v5.0 https://github.com/mongodb/mongo/commit/ea79d55381c353e84cd673c4b21deb0b0ea4826e xgen-internal-githook commented on Thu, 2 Jun 2022 11:27:22 +0000: Author: {'name': 'Timour Katchaounov', 'email': 'timour.katchaounov@mongodb.com', 'username': 'timourk'} Message: SERVER-66379 $or to $in conversion flawed (cherry picked from commit 951197b3834d509d7903efa4a66c0e9f79235262) Branch: v6.0 https://github.com/mongodb/mongo/commit/b499c915d1c21f063548c96d5d547dcfcda55754 xgen-internal-githook commented on Tue, 31 May 2022 15:18:28 +0000: Author: {'name': 'Timour Katchaounov', 'email': 'timour.katchaounov@mongodb.com', 'username': 'timourk'} Message: SERVER-66379 $or to $in conversion flawed Branch: master https://github.com/mongodb/mongo/commit/951197b3834d509d7903efa4a66c0e9f79235262 JIRAUSER1258247 commented on Thu, 26 May 2022 09:46:29 +0000: It turns out the collation is crucial. This is a reproducible test case: db.createCollection("some"); db.getCollection("some").find({ "$or" : [ { "x" : "a" }, { "x" : "b" }, { "x" : /c/ }] }).sort({ name: 1 }).collation({ locale: 'en_US'}) JIRAUSER1258247 commented on Thu, 26 May 2022 09:39:03 +0000: Update: I read the original thread on Stackoverflow, and tested the complete example in the thread. Ineed, the original much bigger query results in the reported assertion. So there is a bug, but the test case here seems to have been oversimplified. I will simplify it a bit before continuing work on the bug. JIRAUSER1258247 commented on Thu, 26 May 2022 09:13:17 +0000: Unfortunately I cannot reproduce the problem on neither master, nor v5.0. This is what I tried: test> db.createCollection("some"); { ok: 1 } test> db.getCollection("some").aggregate({$match: { "$or" : [ { "x" : "a" }, { "x" : "b" }, { "x" : /c/ }] } }) test> db.some.insertOne({x:"a"}) { acknowledged: true, insertedId: ObjectId("628f440bda50c4aecee984f3") } test> db.getCollection("some").aggregate({$match: { "$or" : [ { "x" : "a" }, { "x" : "b" }, { "x" : /c/ }] } }) [ { _id: ObjectId("628f440bda50c4aecee984f3"), x: 'a' } ] daniel.hegener@gmx.net could you please provide exact instructions how to reproduce - exact version (or commit), how it was built, complete script. JIRAUSER1256534 commented on Wed, 11 May 2022 11:35:49 +0000: https://stackoverflow.com/questions/69098410/mongodb-failed-with-error-failed-to-optimize-expression

Steps to Reproduce