An error occurs if the format of the timestamp field is not defined when creating the data source.

[ufoscw]

Describe the bug
An error occurs if the format of the timestamp field is not defined when creating the data source.

To Reproduce
Steps to reproduce the behavior:

1. Go to mysql workbench
2. execute query

select CAST("2017-08-29" as DATE) as dt;

3. click chart preview
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

{
   "code":"EG0001",
   "message":"Fail to process response : [{\"error\":\"Unknown exception\",\"errorMessage\":\"Need to specify dimension specs, for now\",\"errorClass\":\"java.lang.IllegalArgumentException\",\"errorStack\":[\"io.druid.server.BrokerQueryResource.loadToIndex(BrokerQueryResource.java:417)\",\"sun.reflect.GeneratedMethodAccessor370.invoke(Unknown Source)\",\"sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\",\"java.lang.reflect.Method.invoke(Method.java:498)\",\"com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)\",\"com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:205)\",\"com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)\",\"com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302)\",\"com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)\",\"com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)\",\"... more\"],\"host\":\"metatron-hadoop-03:8082\",\"serviceName\":\"druid/prod/broker\"}]",
   "details":"QueryTimeExcetpion: [{\"error\":\"Unknown exception\",\"errorMessage\":\"Need to specify dimension specs, for now\",\"errorClass\":\"java.lang.IllegalArgumentException\",\"errorStack\":[\"io.druid.server.BrokerQueryResource.loadToIndex(BrokerQueryResource.java:417)\",\"sun.reflect.GeneratedMethodAccessor370.invoke(Unknown Source)\",\"sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\",\"java.lang.reflect.Method.invoke(Method.java:498)\",\"com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)\",\"com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:205)\",\"com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)\",\"com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302)\",\"com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)\",\"com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)\",\"... more\"],\"host\":\"metatron-hadoop-03:8082\",\"serviceName\":\"druid/prod/broker\"}]"
}

Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.