# C.53 LiquibaseDiffTask The `LiquibaseDiffTask` creates a diff between two databases. Will output the changes needed to convert the reference database to the state of the database. Table C.64:聽Attributes NameTypeDescriptionDefaultRequired`jar``String`Location of the Liquibase jar file.n/aYes`classpath``String`Additional classpath entries.n/aYes`changeLogFile``String`Location of the changelog file in which the changes get written or read from.n/aYes`username``String`The username needed to connect to the database.n/aYes`password``String`The password needed to connect to the database.n/aYes`url``String`The JDBC Url representing the database datasource, e.g `jdbc:mysql://localhost/mydatabase`n/aYes`referenceUsername``String`The username needed to connect to the reference database.n/aYes`referencePassword``String`The password needed to connect to the reference database.n/aYes`referenceUrl``String`The JDBC Url representing the database reference datasource, e.g `jdbc:mysql://localhost/refdatabase`n/aYes`display``Boolean`Whether to display the output of the command. Only used if `passthru` isn't true.falseNo`passthru``Boolean`Whether to use PHP's `passthru()` function instead of `exec()`. True by default for backwards compatibility. When true, the attributes `display`, `outputProperty` and `checkReturn`are ignored.trueNo`checkreturn``Boolean`Whether to check the return code of the execution, throws a BuildException when returncode != 0.falseNo`outputProperty``String`Property name to set output value to from the execution. Ignored if `passthru` attribute is true.n/aNo C.53.1 Example ``` <liquibase-diff jar="/usr/local/lib/liquibase/liquibase.jar" classpathref="/usr/local/lib/liquibase/lib/mysql-connector-java-5.1.15-bin.jar" changelogFile="./changelogTest.xml" username="liquibase" password="liquibase" url="jdbc:mysql://localhost/mydatabase" referenceUsername="liquibase" referencePassword="liquibase" referenceUrl="jdbc:mysql://localhost/refdatabase" /> ``` C.53.2 Supported Nested Tags - `parameter` Same as for [Section聽C.50](apcs50.html "C.50 LiquibaseTask"). - `property` Same as for [Section聽C.50](apcs50.html "C.50 LiquibaseTask").