KB-1830 "ORA-00923: FROM keyword not found where expected" error thrown when using Oracle as the database


When using Tomcat as the application server and a supported version of Oracle as the database, the application server fails to start with the following error in the logs:

WARNING [localhost-startStop-1] org.apache.naming.NamingContext.lookup Unexpected exception resolving reference java.sql.SQLException: Cannot create PoolableConnectionFactory (ORA-00923: FROM keyword not found where expected ) at org.apache.tomcat.dbcp.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2385)


This occurs when the following line in suite.xml (located in <APPIAN_HOME>\tomcat\apache-tomcat\conf\Catalina\localhost) reads as follows:

validationQuery="SELECT 1"


Change the above line in suite.xml to the following:

validationQuery="SELECT 1 FROM dual"

Make sure all other values in suite.xml are formatted as seen in the Configuring Relational Databases documentation.

Affected Versions

This article applies to Appian 18.3 and later using Oracle as the database.

Last reviewed: January 2019