Add transaction report generation code

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=167311547

java/google/registry/reporting/sql/total_nameservers.sql

@@ -0,0 +1,56 @@
+#standardSQL
+  -- Copyright 2017 The Nomulus Authors. All Rights Reserved.
+  --
+  -- Licensed under the Apache License, Version 2.0 (the "License");
+  -- you may not use this file except in compliance with the License.
+  -- You may obtain a copy of the License at
+  --
+  --     http://www.apache.org/licenses/LICENSE-2.0
+  --
+  -- Unless required by applicable law or agreed to in writing, software
+  -- distributed under the License is distributed on an "AS IS" BASIS,
+  -- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  -- See the License for the specific language governing permissions and
+  -- limitations under the License.
+
+  -- Determine the number of referenced nameservers for a registrar's domains.
+
+  -- We count the number of unique hosts under each tld-registrar combo by
+  -- collecting all domains' listed hosts that were still valid at the
+  -- end of the reporting month.
+
+SELECT
+  tld,
+  registrarName AS registrar_name,
+  'TOTAL_NAMESERVERS' AS metricName,
+  COUNT(fullyQualifiedHostName) AS metricValue
+FROM
+  `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%HOSTRESOURCE_TABLE%` AS host_table
+JOIN (
+  SELECT
+    __key__.name AS clientId,
+    registrarName
+  FROM
+    `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%REGISTRAR_TABLE%`
+  WHERE
+    type = 'REAL'
+    OR type = 'INTERNAL') AS registrar_table
+ON
+  currentSponsorClientId = registrar_table.clientId
+JOIN (
+  SELECT
+    tld,
+    hosts.name AS referencedHostName
+  FROM
+    `%PROJECT_ID%.%DATASTORE_EXPORT_DATA_SET%.%DOMAINBASE_TABLE%`,
+    UNNEST(nsHosts) AS hosts
+  WHERE _d = 'DomainResource'
+  AND creationTime <= TIMESTAMP("%LATEST_REPORT_TIME%")
+  AND deletionTime > TIMESTAMP("%LATEST_REPORT_TIME%") ) AS domain_table
+ON
+  host_table.__key__.name = domain_table.referencedHostName
+WHERE creationTime <= TIMESTAMP("%LATEST_REPORT_TIME%")
+AND deletionTime > TIMESTAMP("%LATEST_REPORT_TIME%")
+GROUP BY tld, registrarName
+ORDER BY tld, registrarName
+