§Play Slick FAQ
§What version should I use?
Have a look at the compatibility matrix to know what version you should be using.
§play.db.pool is ignored
It’s indeed the case. Changing the value of play.db.pool won’t affect what connection pool Slick is going to use. The reason is simply that Play Slick module currently doesn’t support using a different connection pool than HikariCP.
§Changing the connection pool used by Slick
While Slick allows using a different connection pool than HikariCP(though, Slick currently only offers built-in support for HikariCP, and requires you to provide an implementation of JdbcDataSourceFactory if you want to use a different connection pool), Play Slick currently doesn’t allow using a different connection pool than HikariCP. If you find yourself needing this feature, you can try to drop us a note on playframework-dev.
§A binding to play.api.db.DBApi was already configured
If you get the following exception when starting your Play application:
1) A binding to play.api.db.DBApi was already configured at play.api.db.slick.evolutions.EvolutionsModule.bindings:
Binding(interface play.api.db.DBApi to ConstructionTarget(class play.api.db.slick.evolutions.internal.DBApiAdapter) in interface javax.inject.Singleton).
at play.api.db.DBModule.bindings(DBModule.scala:25):
Binding(interface play.api.db.DBApi to ProviderConstructionTarget(class play.api.db.DBApiProvider))
It is very likely that you have enabled the jdbc plugin, and that doesn’t really make sense if you are using Slick for accessing your databases. To fix the issue simply remove the Play jdbc component from your project’s build.
Another possibility is that there is another Play module that is binding DBApi to some other concrete implementation. This means that you are still trying to use Play Slick together with another Play module for database access, which is likely not what you want.
§Play throws java.lang.ClassNotFoundException: org.h2.tools.Server
If you get the following exception when starting your Play application:
java.lang.ClassNotFoundException: org.h2.tools.Server
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
...
It means you are trying to use a H2 database, but have forgot to add a dependency to it in your project’s build. Fixing the problem is simple, just add the missing dependency in your project’s build, e.g.,
"com.h2database" % "h2" % "${H2_VERSION}" // replace `${H2_VERSION}` with an actual version number