[SQL] Logical comparison on Strings

[kumar]

Dear Friends,   Postgres 7.3.2 on Linux 7.   I want to compare to columns and get the logical result as follows.   C1 is 'YNYNY' . C2 is 'NNYYY'.   I want to compare like AND and OR operators.   C1 AND C2 should give result like NNYNY. C1 OR C2 should give result like YNYYY.   Please shed some light.   Thanks Kumar