No grammar constraints (DTD or XML Schema) referenced in the document.

No grammar constraints (DTD or XML Schema) referenced in the document.

이런 warning이 떠서 검색을 해봤더니 아래와 같이 <!DOCTYPE configuration>을 추가를 해주니 사라졌다.

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE configuration>

<configuration>

<include resource="org/springframework/boot/logging/logback/base.xml"/>

<!-- log4jdbc-log4j2 -->

<logger name="jdbc.sqlonly" level="DEBUG"/>

<logger name="jdbc.sqltiming" level="INFO"/>

<logger name="jdbc.audit" level="WARN"/>

<logger name="jdbc.resultset" level="ERROR"/>

<logger name="jdbc.resultsettable" level="ERROR"/>

<logger name="jdbc.connection" level="INFO"/>

</configuration>