DATAMONGO-2059 - Document count helper restrictions for geo commands inside of transactions.

src/main/asciidoc/reference/client-session-transactions.adoc

@@ -297,6 +297,7 @@ error occurs here.
 <3> An error outside the transaction flow has no affect on the previous transactional execution.
 ====
 
+[[mongo.transactions.behavior]]
 == Special behavior inside transactions
 
 Inside transactions, MongoDB server has a slightly different behavior.
@@ -321,6 +322,14 @@ The server responds with _error 50851_ when issuing a `count` command inside of
 Once `MongoTemplate` detects an active transaction, all exposed `count()` methods are converted and delegated to the
 aggregation framework using `$match` and `$count` operators, preserving `Query` settings, such as `collation`.
 
+Restrictions apply when using geo commands inside of the aggregation count helper. The following operators cannot be used and must be replaced with a different operator:
+
+* `$where` -> `$expr`
+* `$near` -> `$geoWithin` with `$center`
+* `$nearSphere` -> `$geoWithin` with `$centerSphere`
+
+Queries using `Criteria.near(…)` and `Criteria.nearSphere(…)` must be rewritten to `Criteria.within(…)` respective `Criteria.withinSphere(…)`. Same applies for the `near` query keyword in repository query methods that must be changed to `within`. See also MongoDB JIRA ticket https://jira.mongodb.org/browse/DRIVERS-518[DRIVERS-518] for further reference.
+
 The following snippet shows `count` usage inside the session-bound closure:
 
 ====

src/main/asciidoc/reference/mongodb.adoc

@@ -1201,6 +1201,8 @@ template.query(Person.class)  <1>
 
 MongoDB supports GeoSpatial queries through the use of operators such as `$near`, `$within`, `geoWithin`, and `$nearSphere`. Methods specific to geospatial queries are available on the `Criteria` class. There are also a few shape classes (`Box`, `Circle`, and `Point`) that are used in conjunction with geospatial related `Criteria` methods.
 
+NOTE: Using GeoSpatial queries requires attention when used within MongoDB transactions, see <<mongo.transactions.behavior>>.
+
 To understand how to perform GeoSpatial queries, consider the following `Venue` class (taken from the integration tests and relying on the rich `MappingMongoConverter`):
 
 [source,java]
@@ -3083,4 +3085,4 @@ class GridFsClient {
 
 `GridFsOperations` extends `ResourcePatternResolver` and lets the `GridFsTemplate` (for example) to be plugged into an `ApplicationContext` to read Spring Config files from MongoDB database.
 
-include::change-streams.adoc[]
+include::change-streams.adoc[]