With the help of this community I build up this mess of a query for finding a guid:
(because I wanted to know in which ea table it occured what I stumbled upon)
=> search for element ID is missing here!
select ea_guid AS CLASSGUID, Diagram_Type as CLASSTYPE, 't_diagram' as CLASSTABLE, Name, diagram_id as t_id, ea_guid as guddi, 't_diagram' as source
from t_diagram where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, Object_Type as CLASSTYPE, 't_object' as CLASSTABLE, Name, object_id as t_id, ea_guid as guddi, 't_object' as source
from t_object where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Connector' as CLASSTYPE, 't_connector' as CLASSTABLE, Name, connector_id as t_id, ea_guid as guddi, 't_connector' as source
from t_connector where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Stereotypes' as CLASSTYPE, 't_stereotypes' as CLASSTABLE, (stereotype + '&' + appliesto) as Name , '0' as t_id, ea_guid as guddi, 't_stereotypes' as source
from t_stereotypes where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Package' as CLASSTYPE, 't_package' as CLASSTABLE, Name , package_id as t_id, ea_guid as guddi, 't_package' as source from t_package where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Attribute' as CLASSTYPE, 't_attribute' as CLASSTABLE, Name, id as t_id, ea_guid as guddi, 't_attribute' as source from t_attribute where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Operation' as CLASSTYPE, 't_operation' as CLASSTABLE, Name, operationid as t_id, ea_guid as guddi, 't_operation' as source from t_operation where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Attributetag' as CLASSTYPE, 't_attributetag' as CLASSTABLE, (ElementID + '&' + propertyid + '&' + property) as Name, '0' as t_id, ea_guid as guddi, 't_attributetag' as source from t_attributetag where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Objectscenarios' as CLASSTYPE, 't_objectscenarios' as CLASSTABLE, Scenario as Name, object_id as t_id, ea_guid as guddi, 't_objectscenarios' as source from t_objectscenarios where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Operationparams' as CLASSTYPE, 't_objectparams' as CLASSTABLE, Name , operationid as t_id, ea_guid as guddi, 't_operationparams' as source from t_operationparams where ea_guid like '#WC#<Search Term>#WC#'
union
select ea_guid AS CLASSGUID, 'Operationtag' as CLASSTYPE, 't_operationtag' as CLASSTABLE, (ElementID + '&' + propertyid + '&' + property) as Name, '0' as t_id, ea_guid as guddi, 't_operationtag' as source from t_operationtag where ea_guid like '#WC#<Search Term>#WC#'