fixes bug#18164

dev:
qua:

git-svn-id: http://desenvolvimento.rjconsultores.com.br/repositorio/sco/BD/FlyWay/trunk@100012 d1611594-4594-4d17-8e1d-87c2c4800839

src/db/migration/V20200131_1855__mantis18164.sql

@@ -0,0 +1,29 @@
+DECLARE
+    itemExists NUMBER;
+BEGIN
+    itemExists := 0;
+
+    SELECT COUNT(CONSTRAINT_NAME) INTO itemExists 
+    FROM ALL_CONSTRAINTS
+    WHERE UPPER(CONSTRAINT_NAME) = UPPER('UNIQUE_CODANTT');
+
+    IF itemExists > 0 THEN
+    BEGIN
+        EXECUTE IMMEDIATE 'ALTER TABLE PARADA DROP CONSTRAINT UNIQUE_CODANTT';
+        EXECUTE IMMEDIATE 'DROP INDEX UNIQUE_CODANTT;';    
+        exception when others THEN null;
+    END;
+    END IF;
+END;
+/
+DECLARE
+    object_exists exception;
+    except_01408 exception;
+    pragma exception_init (object_exists , -00955);
+    pragma exception_init (except_01408 , -01408);
+BEGIN
+	execute IMMEDIATE 'CREATE UNIQUE INDEX UNIQUE_CODANTT ON PARADA (CASE WHEN ACTIVO = 1 THEN CODANTT ELSE NULL END)';
+	exception 
+		when object_exists THEN null;
+		when except_01408 THEN null;
+END;