Quoted table names containing square brackets need to be regex escaped

Use method from Rails master

Author: aidanharan

lib/active_record/connection_adapters/sqlserver/core_ext/query_methods.rb

@@ -0,0 +1,26 @@
+require 'active_record/relation'
+require 'active_record/version'
+
+module ActiveRecord
+  module ConnectionAdapters
+    module SQLServer
+      module CoreExt
+        module QueryMethods
+
+          private
+
+          # Copy of original from Rails master. This patch can be removed when adapter supports Rails 6.
+          def table_name_matches?(from)
+            table_name = Regexp.escape(table.name)
+            quoted_table_name = Regexp.escape(connection.quote_table_name(table.name))
+            /(?:\A|(?<!FROM)\s)(?:\b#{table_name}\b|#{quoted_table_name})(?!\.)/i.match?(from.to_s)
+          end
+        end
+      end
+    end
+  end
+end
+
+ActiveSupport.on_load(:active_record) do
+  ActiveRecord::Relation.include(ActiveRecord::ConnectionAdapters::SQLServer::CoreExt::QueryMethods)
+end

lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -8,6 +8,7 @@
 require 'active_record/connection_adapters/sqlserver/core_ext/explain_subscriber'
 require 'active_record/connection_adapters/sqlserver/core_ext/attribute_methods'
 require 'active_record/connection_adapters/sqlserver/core_ext/finder_methods'
+require 'active_record/connection_adapters/sqlserver/core_ext/query_methods'
 require 'active_record/connection_adapters/sqlserver/version'
 require 'active_record/connection_adapters/sqlserver/type'
 require 'active_record/connection_adapters/sqlserver/database_limits'