Hi, Below is the script to reproduce the issue. When the SELECT stmt is run, derby raises "An ON clause associated with a JOIN operator is not valid" Show I raise a JIRA defect? CREATE TABLE DATAELEMENT ( ID INTEGER NOT NULL, "DATA" VARCHAR(255) ) ALTER TABLE DATAELEMENT ADD CONSTRAINT DATAELEMENT_PK PRIMARY KEY (ID) CREATE TABLE DATACOLLECTION ( ID INTEGER NOT NULL, "DATA_GROUP" INTEGER NOT NULL ) ALTER TABLE DATACOLLECTION ADD CONSTRAINT DATACOLLECTION_PK PRIMARY KEY (ID) CREATE TABLE DATACOLLECTION_ELEMENTS ( ID_OID INTEGER NOT NULL, ID_EID INTEGER NOT NULL ) ALTER TABLE DATACOLLECTION_ELEMENTS ADD CONSTRAINT DATACOLLECTI8E_PK PRIMARY KEY (ID_OID,ID_EID) CREATE TABLE DATACOLLECTION_ELEMENTSCACHED ( ID_OID INTEGER NOT NULL, ID_EID INTEGER NOT NULL ) ALTER TABLE DATACOLLECTION_ELEMENTSCACHED ADD CONSTRAINT DATACOLLECTIKP_PK PRIMARY KEY (ID_OID,ID_EID) SELECT DISTINCT 'org.jpox.samples.performance.DataCollection' AS JPOXMETADATA,THIS.DATA_GROUP,THIS.ID FROM DATACOLLECTION THIS, DATAELEMENT UNBOUND_E LEFT OUTER JOIN DATAELEMENT UNBOUND_E_DATA ON UNBOUND_E.ID = UNBOUND_E_DATA.ID INNER JOIN DATACOLLECTION_ELEMENTS THIS_ELEMENTS ON THIS_ELEMENTS.ID_OID = THIS.ID INNER JOIN DATAELEMENT UNBOUND_F ON THIS_ELEMENTS.ID_EID = UNBOUND_F.ID WHERE UNBOUND_E_DATA."DATA" = 'Something' AND UNBOUND_E.ID = UNBOUND_F.ID AND (THIS.DATA_GROUP = 1) Regards, Erik Bengtson [De