判斷資料庫能否連線的方式

What validation Query to Use

Validation Query is mandatory to ensure that a connection returned to client code is valid. It has the following requirements:

• It must be the most efficient query
• It must return ONE and only ONE row

To declare it, use the Ubik Web Controler or open /config/datasource.xml and add or modify for your pool the parameter validationQuery:

>

     >validationQuery>

     >...>

>

Database	Query
DB2	SELECT COUNT(*) FROM SYSIBM.SYSTABLES OR SELECT CURRENT TIMESTAMP FROM SYSIBM.SYSDUMMY1
Informix	SELECT COUNT(*) FROM SYSTABLES
Microsoft SQL Server	SELECT 1
MySQL	SELECT 1
Oracle	SELECT 1 FROM DUAL
PointBase	SELECT COUNT(*) FROM SYSTABLES
PostgreSQL	SELECT 1
Progress	SELECT COUNT(*) FROM SYSTABLES
Sybase	SELECT 1