loader.incrementalThreads=true
loader.incrementalThreadPoolSize=10

otherJob.incrementalLoader1.class = edu.internet2.middleware.grouper.app.loader.GrouperLoaderIncrementalJob
otherJob.incrementalLoader1.quartzCron = 0 * * * * ?
otherJob.incrementalLoader1.databaseName=warehouse
otherJob.incrementalLoader1.tableName=myincrementaltable
 
otherJob.incrementalLoader2.class = edu.internet2.middleware.grouper.app.loader.GrouperLoaderIncrementalJob
otherJob.incrementalLoader2.quartzCron = 0 * * * * ?
otherJob.incrementalLoader2.databaseName=warehouse2
otherJob.incrementalLoader2.tableName=myincrementaltable

HSQLDB:
 
CREATE TABLE myincrementaltable
(
    id INTEGER NOT NULL,
    subject_id VARCHAR(255),
    subject_identifier VARCHAR(255),
    subject_id_or_identifier VARCHAR(255),
    source_id VARCHAR(255),
    loader_group_name VARCHAR(1024) NOT NULL,
    timestamp BIGINT NOT NULL,
    completed_timestamp BIGINT,
    PRIMARY KEY (id)
);

Example of SQL_SIMPLE using Oracle (loader table has a group name field to allow multiple SQL_SIMPLE jobs):
 
Say you have a loader table that looks like the following:
 
CREATE TABLE myloadertable
(
    subject_id VARCHAR(255),
    group_name VARCHAR(255)
);
 
With the following incremental table:
 
CREATE TABLE myincrementaltable
(
    id NUMBER NOT NULL,
    subject_id VARCHAR(255),
    subject_identifier VARCHAR(255),
    subject_id_or_identifier VARCHAR(255),
    source_id VARCHAR(255),
    loader_group_name VARCHAR(1024) NOT NULL,
    timestamp NUMBER NOT NULL,
    completed_timestamp NUMBER,
    PRIMARY KEY (id)
);
 
And a sequence for the primary key on the incremental table:
 
CREATE SEQUENCE myincrementaltable_seq;
 
And the following loader job:
addRootStem("test", "test")
addGroup("test", "loader1", "loader1")
groupAddType("test:loader1", "grouperLoader")
setGroupAttr("test:loader1", "grouperLoaderDbName", "grouper")
setGroupAttr("test:loader1", "grouperLoaderType", "SQL_SIMPLE")
setGroupAttr("test:loader1", "grouperLoaderScheduleType", "START_TO_START_INTERVAL")
setGroupAttr("test:loader1", "grouperLoaderQuery", "select subject_id from myloadertable")
setGroupAttr("test:loader1", "grouperLoaderIntervalSeconds", "86400")
 
Assuming this is on the same database as Grouper, you could add the following configuration in grouper-loader.properties (run every 5 seconds):
otherJob.incrementalLoader1.class = edu.internet2.middleware.grouper.app.loader.GrouperLoaderIncrementalJob
otherJob.incrementalLoader1.quartzCron = 0/5 * * * * ?
otherJob.incrementalLoader1.databaseName=grouper
otherJob.incrementalLoader1.tableName=myincrementaltable
 
And the following trigger:
 
CREATE OR REPLACE TRIGGER mytrigger
AFTER INSERT OR DELETE OR UPDATE ON myloadertable
FOR EACH ROW
DECLARE
  timemillis NUMBER;
BEGIN
  select extract(day from(sys_extract_utc(systimestamp) - to_timestamp('1970-01-01', 'YYYY-MM-DD'))) * 86400000 
     + to_number(to_char(sys_extract_utc(systimestamp), 'SSSSSFF3')) into timemillis from dual;
  IF (:new.subject_id is not null) THEN
    INSERT INTO myincrementaltable (id, subject_id, loader_group_name, timestamp) values (myincrementaltable_seq.nextval, :new.subject_id, :new.group_name, timemillis);
  END IF;
  IF (:old.subject_id is not null) THEN
    INSERT INTO myincrementaltable (id, subject_id, loader_group_name, timestamp) values (myincrementaltable_seq.nextval, :old.subject_id, :old.group_name, timemillis);
   END IF;
END;