Resolves Mismatch in pathway_event_cohort DDL (#1419)

* WebAPI-975 Extract Cohort Characterization analysis to external package

* fixes SQL injection vulnerability

* Resolves Mismatch in pathway_event_cohort DDL between sql server and postgresql.

src/main/resources/db/migration/sqlserver/V2.6.0.20180906220021__pathway_analysis.sql

@@ -38,7 +38,6 @@ CREATE TABLE ${ohdsiSchema}.pathway_event_cohort
   name                 VARCHAR(255) NOT NULL,
   cohort_definition_id INTEGER NOT NULL,
   pathway_analysis_id  INTEGER NOT NULL,
-  is_deleted           INTEGER DEFAULT 0,
 	CONSTRAINT [PK_pathway_event_cohort] PRIMARY KEY (id),
 	CONSTRAINT FK_pec_cd_id
 		FOREIGN KEY (cohort_definition_id)

src/main/resources/db/migration/sqlserver/V2.8.0.20200116134252__remove_obsolete_field_pathway_event_cohort_deleted_id.sql

@@ -0,0 +1,13 @@
+-- at first removing default value
+declare @command nvarchar(1000)
+select @command = 'ALTER TABLE ${ohdsiSchema}.pathway_event_cohort DROP CONSTRAINT IF EXISTS ' + d.name
+from sys.tables t
+  join sys.default_constraints d on d.parent_object_id = t.object_id
+  join sys.columns c on c.object_id = t.object_id and c.column_id = d.parent_column_id
+where
+  t.name = 'pathway_event_cohort'
+  and t.schema_id = schema_id('${ohdsiSchema}')
+  and c.name = 'is_deleted';
+execute (@command)
+
+ALTER TABLE ${ohdsiSchema}.pathway_event_cohort DROP COLUMN IF EXISTS is_deleted;