VS2005設置Unicode或ASCII字符集問題

在做VC連接數據庫操作時報錯如下：

e:\recv-data\inserttodb\pgdb.cpp(213) : error C2664: 'SQLConnectW' : cannot convert parameter 2 from 'SQLCHAR *' to 'SQLWCHAR *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
e:\recv-data\inserttodb\pgdb.cpp(266) : error C2664: 'SQLExecDirectW' : cannot convert parameter 2 from 'SQLCHAR *' to 'SQLWCHAR *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
e:\recv-data\inserttodb\pgdb.cpp(284) : error C2664: 'SQLExecDirectW' : cannot convert parameter 2 from 'SQLCHAR *' to 'SQLWCHAR *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
e:\recv-data\inserttodb\pgdb.cpp(300) : error C2664: 'SQLExecDirectW' : cannot convert parameter 2 from 'SQLCHAR *' to 'SQLWCHAR *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast

原因：
VS2005中開發程序時，默認的字符集是Unicode。所以如果程序中使用字符串常量時一定要顯示轉換爲Unicode型，否則編譯時報錯

解決方法：
項目菜單--項目屬性(最後一個)--配置屬性--常規--項目默認值--字符集，將使用Unicode字符集改爲未設置即可。