INT-4262: Fix SQL scripts for IF EXISTS clause

JIRA: https://jira.spring.io/browse/INT-4262

Since MySQL doesn't have `IF EXISTS` for `DROP INDEX`.
And on the other hand the entire `DROP TABLE` takes care about indexes as well,
we don't need the `DROP INDEX` command for mysql.properties
* Add `NODROPINDEX` variable to the `mysql.properties`
* Tweak `destroy.sql.vpp` to leverage `NODROPINDEX`

Author: artembilan

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-db2.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
- DROP SEQUENCE INT_MESSAGE_SEQ ;
+DROP SEQUENCE INT_MESSAGE_SEQ ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-derby.sql

@@ -8,3 +8,4 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-h2.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP IF EXISTS;
 DROP TABLE  INT_GROUP_TO_MESSAGE IF EXISTS;
 DROP TABLE  INT_LOCK IF EXISTS;
 DROP TABLE  INT_CHANNEL_MESSAGE IF EXISTS;
- DROP SEQUENCE INT_MESSAGE_SEQ IF EXISTS;
+DROP SEQUENCE INT_MESSAGE_SEQ IF EXISTS;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-hsqldb.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP IF EXISTS;
 DROP TABLE  INT_GROUP_TO_MESSAGE IF EXISTS;
 DROP TABLE  INT_LOCK IF EXISTS;
 DROP TABLE  INT_CHANNEL_MESSAGE IF EXISTS;
- DROP SEQUENCE INT_MESSAGE_SEQ IF EXISTS;
+DROP SEQUENCE INT_MESSAGE_SEQ IF EXISTS;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-mysql.sql

@@ -1,10 +1,8 @@
 -- Autogenerated: do not edit this file
 
-DROP INDEX IF EXISTS INT_MESSAGE_IX1 ;
-DROP INDEX IF EXISTS INT_CHANNEL_MSG_DATE_IDX ;
-DROP INDEX IF EXISTS INT_CHANNEL_MSG_PRIORITY_IDX ;
 DROP TABLE IF EXISTS INT_MESSAGE ;
 DROP TABLE IF EXISTS INT_MESSAGE_GROUP ;
 DROP TABLE IF EXISTS INT_GROUP_TO_MESSAGE ;
 DROP TABLE IF EXISTS INT_LOCK ;
 DROP TABLE IF EXISTS INT_CHANNEL_MESSAGE ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-oracle.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
- DROP SEQUENCE INT_MESSAGE_SEQ ;
+DROP SEQUENCE INT_MESSAGE_SEQ ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-postgresql.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
- DROP SEQUENCE INT_MESSAGE_SEQ ;
+DROP SEQUENCE INT_MESSAGE_SEQ ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-sqlserver.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
- DROP SEQUENCE INT_MESSAGE_SEQ ;
+DROP SEQUENCE INT_MESSAGE_SEQ ;
+

spring-integration-jdbc/src/main/resources/org/springframework/integration/jdbc/schema-drop-sybase.sql

@@ -8,4 +8,5 @@ DROP TABLE  INT_MESSAGE_GROUP ;
 DROP TABLE  INT_GROUP_TO_MESSAGE ;
 DROP TABLE  INT_LOCK ;
 DROP TABLE  INT_CHANNEL_MESSAGE ;
- DROP SEQUENCE INT_MESSAGE_SEQ ;
+DROP SEQUENCE INT_MESSAGE_SEQ ;
+

spring-integration-jdbc/src/main/sql/destroy.sql.vpp

@@ -1,9 +1,18 @@
+#if(!${NODROPINDEX})
 DROP INDEX $!{IFEXISTSBEFORE} INT_MESSAGE_IX1 $!{IFEXISTS};
+#end
+#if(!${NODROPINDEX})
 DROP INDEX $!{IFEXISTSBEFORE} INT_CHANNEL_MSG_DATE_IDX $!{IFEXISTS};
+#end
+#if(!${NODROPINDEX})
 DROP INDEX $!{IFEXISTSBEFORE} INT_CHANNEL_MSG_PRIORITY_IDX $!{IFEXISTS};
+#end
 DROP TABLE $!{IFEXISTSBEFORE} INT_MESSAGE $!{IFEXISTS};
 DROP TABLE $!{IFEXISTSBEFORE} INT_MESSAGE_GROUP $!{IFEXISTS};
 DROP TABLE $!{IFEXISTSBEFORE} INT_GROUP_TO_MESSAGE $!{IFEXISTS};
 DROP TABLE $!{IFEXISTSBEFORE} INT_LOCK $!{IFEXISTS};
 DROP TABLE $!{IFEXISTSBEFORE} INT_CHANNEL_MESSAGE $!{IFEXISTS};
-#if(${INT_MESSAGE_SEQ}) DROP SEQUENCE INT_MESSAGE_SEQ $!{IFEXISTS};#end
+#if(${INT_MESSAGE_SEQ})
+DROP SEQUENCE INT_MESSAGE_SEQ $!{IFEXISTS};
+#end
+

spring-integration-jdbc/src/main/sql/mysql.properties

@@ -12,4 +12,5 @@ TIMESTAMP = DATETIME(6)
 VARCHAR = VARCHAR
 # for generating drop statements...
 SEQUENCE = TABLE
-AUTO_INCREMENT = AUTO_INCREMENT UNIQUE
+AUTO_INCREMENT = AUTO_INCREMENT UNIQUE
+NODROPINDEX = true

spring-integration-jdbc/src/test/java/org/springframework/integration/jdbc/DelayerHandlerRescheduleIntegrationTests.java

@@ -72,6 +72,7 @@ public class DelayerHandlerRescheduleIntegrationTests {
 	public static void init() {
 		dataSource = new EmbeddedDatabaseBuilder()
 				.setType(EmbeddedDatabaseType.H2)
+				.addScript("classpath:/org/springframework/integration/jdbc/schema-drop-h2.sql")
 				.addScript("classpath:/org/springframework/integration/jdbc/schema-h2.sql")
 				.build();
 	}