Don't try to run clauseless index scans on index types that don't support it.  Per report from Marinos Yannikos.
Don't try to run clauseless index scans on index types that don't support
it.  Per report from Marinos Yannikos.

xinzweb/gpdb,greenplum-db/gpdb,royc1/gpdb,edespino/gpdb,jmcatamney/gpdb,kmjungersen/PostgresXL,postmind-net/postgres-xl,kmjungersen/PostgresXL,zaksoup/gpdb,greenplum-db/gpdb,yuanzhao/gpdb,Quikling/gpdb,zaksoup/gpdb,oberstet/postgres-xl,ashwinstar/gpdb,pavanvd/postgres-xl,tangp3/gpdb,Quikling/gpdb,Chibin/gpdb,kaknikhil/gpdb,royc1/gpdb,lintzc/gpdb,snaga/postgres-xl,adam8157/gpdb,ashwinstar/gpdb,techdragon/Postgres-XL,janebeckman/gpdb,50wu/gpdb,cjcjameson/gpdb,pavanvd/postgres-xl,ovr/postgres-xl,CraigHarris/gpdb,kaknikhil/gpdb,edespino/gpdb,randomtask1155/gpdb,tpostgres-projects/tPostgres,atris/gpdb,Quikling/gpdb,edespino/gpdb,foyzur/gpdb,Chibin/gpdb,oberstet/postgres-xl,greenplum-db/gpdb,zeroae/postgres-xl,zeroae/postgres-xl,lintzc/gpdb,tpostgres-projects/tPostgres,yuanzhao/gpdb,kaknikhil/gpdb,tangp3/gpdb,rubikloud/gpdb,yuanzhao/gpdb,techdragon/Postgres-XL,xuegang/gpdb,zaksoup/gpdb,0x0FFF/gpdb,jmcatamney/gpdb,arcivanov/postgres-xl,yuanzhao/gpdb,oberstet/postgres-xl,lpetrov-pivotal/gpdb,rubikloud/gpdb,ahachete/gpdb,kaknikhil/gpdb,ahachete/gpdb,rvs/gpdb,arcivanov/postgres-xl,atris/gpdb,ovr/postgres-xl,ovr/postgres-xl,chrishajas/gpdb,Chibin/gpdb,edespino/gpdb,atris/gpdb,ahachete/gpdb,Chibin/gpdb,chrishajas/gpdb,chrishajas/gpdb,Postgres-XL/Postgres-XL,lintzc/gpdb,adam8157/gpdb,yuanzhao/gpdb,rubikloud/gpdb,Chibin/gpdb,lisakowen/gpdb,jmcatamney/gpdb,royc1/gpdb,0x0FFF/gpdb,randomtask1155/gpdb,zeroae/postgres-xl,randomtask1155/gpdb,snaga/postgres-xl,janebeckman/gpdb,Quikling/gpdb,edespino/gpdb,janebeckman/gpdb,xinzweb/gpdb,tpostgres-projects/tPostgres,Postgres-XL/Postgres-XL,randomtask1155/gpdb,ovr/postgres-xl,zaksoup/gpdb,greenplum-db/gpdb,rvs/gpdb,lpetrov-pivotal/gpdb,CraigHarris/gpdb,tangp3/gpdb,foyzur/gpdb,pavanvd/postgres-xl,Quikling/gpdb,pavanvd/postgres-xl,Chibin/gpdb,royc1/gpdb,randomtask1155/gpdb,lintzc/gpdb,xuegang/gpdb,yazun/postgres-xl,rubikloud/gpdb,lintzc/gpdb,cjcjameson/gpdb,yazun/postgres-xl,yuanzhao/gpdb,zeroae/postgres-xl,Postgres-XL/Postgres-XL,oberstet/postgres-xl,foyzur/gpdb,xinzweb/gpdb,cjcjameson/gpdb,Postgres-XL/Postgres-XL,kaknikhil/gpdb,adam8157/gpdb,0x0FFF/gpdb,chrishajas/gpdb,ahachete/gpdb,xinzweb/gpdb,randomtask1155/gpdb,lpetrov-pivotal/gpdb,atris/gpdb,lintzc/gpdb,arcivanov/postgres-xl,0x0FFF/gpdb,tpostgres-projects/tPostgres,snaga/postgres-xl,chrishajas/gpdb,50wu/gpdb,foyzur/gpdb,Quikling/gpdb,yazun/postgres-xl,xuegang/gpdb,royc1/gpdb,0x0FFF/gpdb,tangp3/gpdb,lpetrov-pivotal/gpdb,lisakowen/gpdb,janebeckman/gpdb,tangp3/gpdb,tpostgres-projects/tPostgres,lisakowen/gpdb,kaknikhil/gpdb,ahachete/gpdb,royc1/gpdb,cjcjameson/gpdb,ashwinstar/gpdb,Chibin/gpdb,kaknikhil/gpdb,0x0FFF/gpdb,chrishajas/gpdb,ashwinstar/gpdb,rubikloud/gpdb,yazun/postgres-xl,yuanzhao/gpdb,edespino/gpdb,rvs/gpdb,kaknikhil/gpdb,ashwinstar/gpdb,CraigHarris/gpdb,50wu/gpdb,CraigHarris/gpdb,50wu/gpdb,rubikloud/gpdb,zaksoup/gpdb,adam8157/gpdb,royc1/gpdb,rubikloud/gpdb,atris/gpdb,yuanzhao/gpdb,xuegang/gpdb,kaknikhil/gpdb,cjcjameson/gpdb,edespino/gpdb,edespino/gpdb,cjcjameson/gpdb,janebeckman/gpdb,50wu/gpdb,xinzweb/gpdb,kmjungersen/PostgresXL,cjcjameson/gpdb,edespino/gpdb,xinzweb/gpdb,Quikling/gpdb,lisakowen/gpdb,Chibin/gpdb,lisakowen/gpdb,zaksoup/gpdb,greenplum-db/gpdb,cjcjameson/gpdb,yazun/postgres-xl,oberstet/postgres-xl,techdragon/Postgres-XL,janebeckman/gpdb,lintzc/gpdb,jmcatamney/gpdb,rvs/gpdb,atris/gpdb,xuegang/gpdb,atris/gpdb,atris/gpdb,lisakowen/gpdb,greenplum-db/gpdb,adam8157/gpdb,snaga/postgres-xl,jmcatamney/gpdb,postmind-net/postgres-xl,kmjungersen/PostgresXL,kaknikhil/gpdb,lpetrov-pivotal/gpdb,postmind-net/postgres-xl,Chibin/gpdb,lintzc/gpdb,rvs/gpdb,janebeckman/gpdb,rubikloud/gpdb,lpetrov-pivotal/gpdb,ahachete/gpdb,kmjungersen/PostgresXL,cjcjameson/gpdb,50wu/gpdb,xinzweb/gpdb,foyzur/gpdb,zeroae/postgres-xl,tangp3/gpdb,50wu/gpdb,foyzur/gpdb,janebeckman/gpdb,lpetrov-pivotal/gpdb,rvs/gpdb,chrishajas/gpdb,snaga/postgres-xl,greenplum-db/gpdb,yuanzhao/gpdb,Postgres-XL/Postgres-XL,foyzur/gpdb,postmind-net/postgres-xl,zaksoup/gpdb,CraigHarris/gpdb,CraigHarris/gpdb,rvs/gpdb,xuegang/gpdb,ahachete/gpdb,xuegang/gpdb,zaksoup/gpdb,rvs/gpdb,royc1/gpdb,lisakowen/gpdb,arcivanov/postgres-xl,tangp3/gpdb,50wu/gpdb,tangp3/gpdb,techdragon/Postgres-XL,postmind-net/postgres-xl,ashwinstar/gpdb,lpetrov-pivotal/gpdb,xuegang/gpdb,pavanvd/postgres-xl,lisakowen/gpdb,rvs/gpdb,edespino/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,xuegang/gpdb,cjcjameson/gpdb,yuanzhao/gpdb,arcivanov/postgres-xl,0x0FFF/gpdb,randomtask1155/gpdb,Quikling/gpdb,techdragon/Postgres-XL,adam8157/gpdb,CraigHarris/gpdb,janebeckman/gpdb,ahachete/gpdb,rvs/gpdb,arcivanov/postgres-xl,randomtask1155/gpdb,lintzc/gpdb,jmcatamney/gpdb,adam8157/gpdb,chrishajas/gpdb,Quikling/gpdb,foyzur/gpdb,ovr/postgres-xl,CraigHarris/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,0x0FFF/gpdb,xinzweb/gpdb,adam8157/gpdb,Quikling/gpdb,CraigHarris/gpdb,janebeckman/gpdb,Chibin/gpdb