Reject Limit parameter using String-based queries.

Document limitations, add test cases for derived queries.

Closes #1654

src/main/antora/modules/ROOT/pages/jdbc/query-methods.adoc

@@ -169,6 +169,9 @@ Properties that don't have a matching column in the result will not be set.
 The query is used for populating the aggregate root, embedded entities and one-to-one relationships including arrays of primitive types which get stored and loaded as SQL-array-types.
 Separate queries are generated for maps, lists, sets and arrays of entities.
 
+WARNING: Note that String-based queries do not support pagination nor accept `Sort`, `PageRequest`, and `Limit` as a query parameter as for these queries the query would be required to be rewritten.
+If you want to apply limiting, please express this intent using SQL and bind the appropriate parameters to the query yourself.
+
 Queries may contain SpEL expressions where bind variables are allowed.
 Such a SpEL expression will get replaced with a bind variable and the variable gets bound to the result of the SpEL expression.
 

src/main/antora/modules/ROOT/pages/r2dbc/query-methods.adoc

@@ -182,6 +182,27 @@ Therefore also fields with auditing annotations do not get updated if they don't
 
 Alternatively, you can add custom modifying behavior by using the facilities described in xref:repositories/custom-implementations.adoc[Custom Implementations for Spring Data Repositories].
 
+[[r2dbc.query-methods.at-query]]
+== Using `@Query`
+
+The following example shows how to use `@Query` to declare a query method:
+
+.Declare a query method by using @Query
+[source,java]
+----
+interface UserRepository extends ReactiveCrudRepository<User, Long> {
+
+  @Query("select firstName, lastName from User u where u.emailAddress = :email")
+  Flux<User> findByEmailAddress(@Param("email") String email);
+}
+----
+
+WARNING: Note that String-based queries do not support pagination nor accept `Sort`, `PageRequest`, and `Limit` as a query parameter as for these queries the query would be required to be rewritten.
+If you want to apply limiting, please express this intent using SQL and bind the appropriate parameters to the query yourself.
+
+NOTE: Spring fully supports Java 8’s parameter name discovery based on the `-parameters` compiler flag.
+By using this flag in your build as an alternative to debug information, you can omit the `@Param` annotation for named parameters.
+
 [[r2dbc.repositories.queries.spel]]
 === Queries with SpEL Expressions