PostgreSQL HA questions

Hello<br /><br /> We're looking for HA PostgreSQL solution,so have a couple of questions:<br /><br /> 1. Is it possible
formultiply PostgreSQL instances (engines,cores) to use same DATA space? For example,to have two PostgreSQL processes
whichwill use same data directory,same files,and same data ? So,if You update some data in some table over
postmaster1,theprocess which uses connection to postmaster2 will 'see' the exact same data in the same table ?<br /><br
/>2. Becouse of vaccuming issues,is it possible to create such a client process which will use two identical tables,and
onreceiving a signal,it will switch between those tables.For example,first a client application uses table1,after some
time,senda signal to process,it will switch using table2,so You can freely vacuum table1 or whatsoever.After vacuuming
done,table1 will sinchronize with table2 and keep up-to-date until You send next signal to application,which will
switchusing table1,so You can vacuum table2.<br /><br /> If any one has any ideas,thoughts ?<br /><br /> Sincerely<br
/><br/> Dragan<br />