Improve JDBC data store schema scripts

Closes gh-982

spring-session/src/main/java/org/springframework/session/jdbc/JdbcOperationsSessionRepository.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2016 the original author or authors.
+ * Copyright 2014-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -105,6 +105,7 @@ import org.springframework.util.StringUtils;
  * );
  *
  * CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+ * CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
  *
  * CREATE TABLE SPRING_SESSION_ATTRIBUTES (
  *  SESSION_ID CHAR(36),

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 ) ENGINE=InnoDB;
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

spring-session/src/main/resources/org/springframework/session/jdbc/schema-sqlite.sql

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 );
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,

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

@@ -8,6 +8,7 @@ CREATE TABLE SPRING_SESSION (
 ) LOCK DATAROWS;
 
 CREATE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (LAST_ACCESS_TIME);
+CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (PRINCIPAL_NAME);
 
 CREATE TABLE SPRING_SESSION_ATTRIBUTES (
 	SESSION_ID CHAR(36) NOT NULL,