Why do we see ORA-00904 Oracle Error in server logs.

Issue

• The ORA-00904 error causes the application not to behave properly.
• Why do we see many ORA-00904 errors in our server logs.

Caused by: java.sql.SQLSyntaxErrorException: ORA-00904: "xx"."xyz": invalid identifier

    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:439)
    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:395)
    at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:802)
    at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:436)
    at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:186)
    at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:521)
    at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:194)
    at oracle.jdbc.driver.T4CStatement.executeForDescribe(T4CStatement.java:853)
    at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1145)
    at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1267)
    at oracle.jdbc.driver.OracleStatement.executeQuery(OracleStatement.java:1469)
    at oracle.jdbc.driver.OracleStatementWrapper.executeQuery(OracleStatementWrapper.java:389)
    at org.jboss.resource.adapter.jdbc.WrappedStatement.executeQuery(WrappedStatement.java:226)
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