Improve performance of analysis 117

Since HAVING clause removes records which don't match obs_month, we can use INNER JOIN here.

This is to address problem in Databricks where small table in LEFT JOIN is not broadcasted when it's on left side.

Related issue #690

inst/sql/sql_server/analyses/117.sql

@@ -2,23 +2,23 @@
 
 --HINT DISTRIBUTE_ON_KEY(stratum_1)
 -- generating date key sequences in a cross-dialect compatible fashion
-with century as (select '19' num union select '20' num), 
+with century as (select '19' num union select '20' num),
 tens as (select '0' num union select '1' num union select '2' num union select '3' num union select '4' num union select '5' num union select '6' num union select '7' num union select '8' num union select '9' num),
 ones as (select '0' num union select '1' num union select '2' num union select '3' num union select '4' num union select '5' num union select '6' num union select '7' num union select '8' num union select '9' num),
 months as (select '01' as num union select '02' num union select '03' num union select '04' num union select '05' num union select '06' num union select '07' num union select '08' num union select '09' num union select '10' num union select '11' num union select '12' num),
 date_keys as (select cast(concat(century.num, tens.num, ones.num,months.num) as int) obs_month from century cross join tens cross join ones cross join months)
 SELECT
-  117 as analysis_id,  
+  117 as analysis_id,
 	CAST(t1.obs_month AS VARCHAR(255)) as stratum_1,
 	cast(null as varchar(255)) as stratum_2, cast(null as varchar(255)) as stratum_3, cast(null as varchar(255)) as stratum_4, cast(null as varchar(255)) as stratum_5,
 	COALESCE(COUNT_BIG(distinct op1.PERSON_ID),0) as count_value
-into @scratchDatabaseSchema@schemaDelim@tempAchillesPrefix_117	
-FROM date_keys t1
-left join
-  (select t2.obs_month, op2.*
-    from @cdmDatabaseSchema.observation_period op2, date_keys t2
-    where year(op2.observation_period_start_date)*100 + month(op2.observation_period_start_date) <= t2.obs_month
-    and year(op2.observation_period_end_date)*100 + month(op2.observation_period_end_date) >= t2.obs_month
-  ) op1 on op1.obs_month = t1.obs_month
+into @scratchDatabaseSchema@schemaDelim@tempAchillesPrefix_117
+from
+  @cdmDatabaseSchema.observation_period op1
+  inner join
+  date_keys t1 on
+    year(op1.observation_period_start_date)*100 + month(op1.observation_period_start_date) <= t1.obs_month
+    and
+    year(op1.observation_period_end_date)*100 + month(op1.observation_period_end_date) >= t1.obs_month
 group by t1.obs_month
 having COALESCE(COUNT_BIG(distinct op1.PERSON_ID),0) > 0;