CREATE TABLE test_a(a integer, b integer);
INSERT INTO test_a VALUES (1, 1);
INSERT INTO test_a VALUES (1, 2);
INSERT INTO test_a VALUES (2, 1);
INSERT INTO test_a VALUES (2, 2);
INSERT INTO test_a VALUES (3, 2);
INSERT INTO test_a VALUES (3, 10);

with
CTE1 as (
        WITH 
            CTE11 as (SELECT a from pg.test_a),
            CTE21 as (select t1.a from CTE11 t1 join CTE11 t2 on t1.a=t2.a),
            CTE31 as (select a from CTE21)
        SELECT CTE31.a FROM CTE21 join CTE31 on CTE31.a=CTE21.a
    )  
select * from CTE1

16:36:28,752 WARN  [org.teiid.CONNECTOR] (Worker13_QueryProcessorQueue114) eYLiZgMIChSF Connector worker process failed for atomic-request=eYLiZgMIChSF.11.2.24: org.teiid.translator.jdbc.JDBCExecutionException: 0 TEIID11008:TEIID11004 Error executing statement(s): [Prepared Values: [] SQL: WITH CTE11 (a) AS (SELECT NULL FROM "public"."test_a" AS g_0), CTE21 (a) AS (SELECT g_0.a FROM CTE11 AS g_0, CTE11 AS g_1 WHERE g_0.a = g_1.a) SELECT g_1.a FROM CTE21 AS g_0, CTE21 AS g_1 WHERE g_1.a = g_0.a]
        at org.teiid.translator.jdbc.JDBCQueryExecution.execute(JDBCQueryExecution.java:131)
        at org.teiid.dqp.internal.datamgr.ConnectorWorkItem.execute(ConnectorWorkItem.java:365)
        at sun.reflect.GeneratedMethodAccessor94.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.teiid.dqp.internal.datamgr.ConnectorManager$1.invoke(ConnectorManager.java:211)
        at com.sun.proxy.$Proxy56.execute(Unknown Source)
        at org.teiid.dqp.internal.process.DataTierTupleSource.getResults(DataTierTupleSource.java:306)
        at org.teiid.dqp.internal.process.DataTierTupleSource$1.call(DataTierTupleSource.java:112)
        at org.teiid.dqp.internal.process.DataTierTupleSource$1.call(DataTierTupleSource.java:108)
        at java.util.concurrent.FutureTask.run(FutureTask.java:262)
        at org.teiid.dqp.internal.process.FutureWork.run(FutureWork.java:65)
        at org.teiid.dqp.internal.process.DQPWorkContext.runInContext(DQPWorkContext.java:276)
        at org.teiid.dqp.internal.process.ThreadReuseExecutor$RunnableWrapper.run(ThreadReuseExecutor.java:119)
        at org.teiid.dqp.internal.process.ThreadReuseExecutor$3.run(ThreadReuseExecutor.java:210)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: org.postgresql.util.PSQLException: ERROR: failed to find conversion function from unknown to text
        at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2157)
        at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1886)
        at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:255)
        at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:555)
        at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:417)
        at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:302)
        at org.jboss.jca.adapters.jdbc.WrappedPreparedStatement.executeQuery(WrappedPreparedStatement.java:504)
        at org.teiid.translator.jdbc.JDBCQueryExecution.execute(JDBCQueryExecution.java:123)
        ... 17 more

with
CTE1 as (
        WITH 
            alias as (SELECT a from pg.test_a),
            alias2 as (select t2.a as a1, t1.a from alias t1 join (SELECT 1 as a) t2 on t1.a=t2.a),
            CTE31 as (select t2.a as a1 from alias2 t2)
        SELECT CTE31.a1 FROM alias2 join CTE31 on CTE31.a1=alias2.a
    ),
CTE2 as (
        WITH 
            alias as (SELECT 1 as a),
            alias2 as (select t2.a a1, t1.a from alias t1 join (SELECT 1 as a) t2 on t1.a=t2.a),
            CTE32 as (select t2.a from alias2 t2)
        SELECT CTE32.a FROM alias2 join CTE32 on CTE32.a=alias2.a
    )  
select * from CTE1 as T1 join CTE2 as T2 on T1.a1=T2.a