prerequisite:
Install Database Browser
Install PostgreSQL (postgresql-9.0.3-1-windows.exe)
Install PostgreSQL OleDB Provider
After switched to PostgreSQL, the query operation failed, and some words in the exception description is unreadable. So I enabled log file of PostgreSQL OleDB Provider by creating LogFile (for full log file path) and LogLevel (REG_DWORD with value 3) values under key [HKEY_LOCAL_MACHINE/SOFTWARE/PostgreSQL/OLE DB Provider]. It turned out to be access denied error.
There is "Len()" function supported by MS Access, but PostgreSQL provides "length()". My solution is creating a function in PostgreSQL.
CREATE or REPLACE FUNCTION Len(IN text) RETURNS integer
AS $$ SELECT length($1) $$
LANGUAGE SQL;
Database Browser is a nice database client tool that can connect to different databases, run query and display results.
SQL Workbench/J is a free, DBMS-independent, cross-platform SQL query tool. It is written in Java.
Eclipse SQL Explorer is a thin SQL client that allows you to query and browse any JDBC compliant database.