improve database not found error

so we can distinguish between the situations where a database doesn't exist, but should, and the situation where we could auto-create a database, but can't because of security

h2/src/main/org/h2/api/ErrorCode.java

@@ -611,13 +611,11 @@ public class ErrorCode {
     public static final int PARAMETER_NOT_SET_1 = 90012;
 
     /**
-     * The error with code <code>90013</code> is thrown when trying to open a
-     * database that does not exist remotely without enabling remote database
-     * creation first, or using the flag IFEXISTS=TRUE, or when trying to access
+     * The error with code <code>90013</code> is thrown when when trying to access
      * a database object with a catalog name that does not match the database
      * name.
      * <pre>
-     * jdbc:h2:./database_that_does_not_exist
+     * SELECT * FROM database_that_does_not_exist.table_name
      * </pre>
      */
     public static final int DATABASE_NOT_FOUND_1 = 90013;
@@ -2052,7 +2050,17 @@ public class ErrorCode {
     public static final int FOR_UPDATE_IS_NOT_ALLOWED_IN_DISTINCT_OR_GROUPED_SELECT = 90145;
 
 
-    // next is 90146
+    /**
+     * The error with code <code>90146</code> is thrown when trying to open a
+     * database that does not exist remotely without enabling remote database
+     * creation first, or using the flag IFEXISTS=TRUE
+     * <pre>
+     * jdbc:h2:./database_that_does_not_exist
+     * </pre>
+     */
+    public static final int DATABASE_NOT_FOUND_2 = 90146;
+    
+    // next is 90147
 
     private ErrorCode() {
         // utility class

h2/src/main/org/h2/engine/Engine.java

@@ -64,7 +64,7 @@ public class Engine implements SessionFactory {
             }
             if (database == null) {
                 if (ifExists && !Database.exists(name)) {
-                    throw DbException.get(ErrorCode.DATABASE_NOT_FOUND_1, name);
+                    throw DbException.get(ErrorCode.DATABASE_NOT_FOUND_2, name);
                 }
                 database = new Database(ci, cipher);
                 opened = true;

h2/src/main/org/h2/message/DbException.java

@@ -587,6 +587,7 @@ public class DbException extends RuntimeException {
             return new JdbcSQLDataException(message, sql, state, errorCode, cause, stackTrace);
         case URL_RELATIVE_TO_CWD:
         case DATABASE_NOT_FOUND_1:
+        case DATABASE_NOT_FOUND_2:
         case TRACE_CONNECTION_NOT_CLOSED:
         case DATABASE_ALREADY_OPEN_1:
         case FILE_CORRUPTED_1:

h2/src/main/org/h2/res/_messages_en.prop

@@ -177,6 +177,7 @@
 90143=Row {1} not found in primary index {0}
 90144=Authenticator not enabled on database {0}
 90145=FOR UPDATE is not allowed in DISTINCT or grouped select
+90146=Database {0} not found, and IFEXISTS=true, so we can't auto-create it
 HY000=General error: {0}
 HY004=Unknown data type: {0}
 HYC00=Feature not supported: {0}